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1.
Phys Rev Lett ; 128(25): 252002, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35802440

RESUMEN

We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.

2.
Phys Rev Lett ; 127(15): 152301, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34678020

RESUMEN

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

3.
Rev Esp Quimioter ; 34(4): 342-352, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34008930

RESUMEN

OBJECTIVE: Spain is one of the European countries most affected by the COVID-19 pandemic. Epidemiologic studies are warranted to improve the disease understanding, evaluate the care procedure and prepare for futures waves. The aim of the study was to describe epidemiologic characteristics associated with hospitalized patients with COVID-19. METHODS: This real-world, observational, multicenter and retrospective study screened all consecutive patients admitted to 8 Spanish private hospitals. Inclusion criteria: hospitalized adults (age≥18 years old) with clinically and radiologically findings compatible with COVID-19 disease from March 1st to April 5th, 2020. Exclusion criteria: patients presenting negative PCR for SARS-CoV-2 during the first 7 days from hospital admission, transfer to a hospital not belonging to the HM consortium, lack of data and discharge against medical advice in emergency departments. RESULTS: One thousand and three hundred thirty-one COVID-19 patients (medium age 66.9 years old; males n= 841, medium length of hospital stayed 8 days, non-survivors n=233) were analyzed. One hundred and fifteen were admitted to intensive care unit (medium length of stay 16 days, invasive mechanical ventilation n= 95, septic shock n= 37 and renal replacement therapy n= 17). Age, male gender, leukocytes, platelets, oxygen saturation, chronic therapy with steroids and treatment with hydroxychloroquine/azithromycin were independent factors associated with mortality. The proportion of patients that survive and received tocilizumab and steroids were lesser and higher respectively than those that die, but their association was not significant. CONCLUSIONS: Overall crude mortality rate was 17.5%, rising up to 36.5% in the subgroup of patients that were admitted to the intensive care unit. Seven factors impact in hospital mortality. No immunomodulatory intervention were associated with in-hospital mortality.


Asunto(s)
COVID-19/mortalidad , COVID-19/terapia , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Comorbilidad , Cuidados Críticos , Femenino , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Respiración Artificial/estadística & datos numéricos , España , Análisis de Supervivencia , Resultado del Tratamiento , Tratamiento Farmacológico de COVID-19
4.
Metabolism ; 115: 154460, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33285180

RESUMEN

BACKGROUND: Reproduction is tightly coupled to body energy and metabolic status. GnRH neurons, master elements and final output pathway for the brain control of reproduction, directly or indirectly receive and integrate multiple metabolic cues to regulate reproductive function. Yet, the molecular underpinnings of such phenomenon remain largely unfolded. AMP-activated protein kinase (AMPK), the fundamental cellular sensor that becomes activated in conditions of energy deficit, has been recently shown to participate in the control of Kiss1 neurons, essential gatekeepers of the reproductive axis, by driving an inhibitory valence in situations of energy scarcity at puberty. However, the contribution of AMPK signaling specifically in GnRH neurons to the metabolic control of reproduction remains unknown. METHODS: Double immunohistochemistry (IHC) was applied to evaluate expression of active (phosphorylated) AMPK in GnRH neurons and a novel mouse line, named GAMKO, with conditional ablation of the AMPK α1 subunit in GnRH neurons, was generated. GAMKO mice of both sexes were subjected to reproductive characterization, with attention to puberty and gonadotropic responses to kisspeptin and metabolic stress. RESULTS: A vast majority (>95%) of GnRH neurons co-expressed pAMPK. Female (but not male) GAMKO mice displayed earlier puberty onset and exaggerated LH (as surrogate marker of GnRH) responses to kisspeptin-10 at the prepubertal age. In adulthood, GAMKO females retained increased LH responsiveness to kisspeptin and showed partial resilience to the inhibitory effects of conditions of negative energy balance on the gonadotropic axis. The modulatory role of AMPK in GnRH neurons required preserved ovarian function, since the differences in LH pulsatility detected between GAMKO and control mice subjected to fasting were abolished in ovariectomized animals. CONCLUSIONS: Altogether, our data document a sex-biased, physiological role of AMPK signaling in GnRH neurons, as molecular conduit of the inhibitory actions of conditions of energy deficit on the female reproductive axis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo Energético/fisiología , Hormona Liberadora de Gonadotropina/metabolismo , Hormona Luteinizante/sangre , Neuronas/metabolismo , Reproducción/fisiología , Proteínas Quinasas Activadas por AMP/genética , Animales , Ciclo Estral/metabolismo , Femenino , Kisspeptinas/farmacología , Masculino , Desnutrición/metabolismo , Ratones , Ratones Noqueados , Neuronas/efectos de los fármacos , Fosforilación , Caracteres Sexuales , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
5.
Sci Rep ; 10(1): 13898, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807904

RESUMEN

In addition to its essential role in the physiological control of longitudinal growth, growth-hormone (GH) is endowed with relevant metabolic functions, including anabolic actions in muscle, lipolysis in adipose-tissue and glycemic modulation. Adult obesity is known to negatively impact GH-axis, thereby promoting a vicious circle that may contribute to the exacerbation of the metabolic complications of overweight. Yet, to what extent early-overnutrition sensitizes the somatotropic-axis to the deleterious effects of obesity remains largely unexplored. Using a rat-model of sequential exposure to obesogenic insults, namely postnatal-overfeeding during lactation and high-fat diet (HFD) after weaning, we evaluated in both sexes the individual and combined impact of these nutritional challenges upon key elements of the somatotropic-axis. While feeding HFD per se had a modest impact on the adult GH-axis, early overnutrition had durable effects on key elements of the somatotropic-system, which were sexually different, with a significant inhibition of pituitary gene expression of GH-releasing hormone-receptor (GHRH-R) and somatostatin receptor-5 (SST5) in males, but an increase in pituitary GHRH-R, SST2, SST5, GH secretagogue-receptor (GHS-R) and ghrelin expression in females. Notably, early-overnutrition sensitized the GH-axis to the deleterious impact of HFD, with a significant suppression of pituitary GH expression in both sexes and lowering of circulating GH levels in females. Yet, despite their similar metabolic perturbations, males and females displayed rather distinct alterations of key somatotropic-regulators/ mediators. Our data document a synergistic effect of postnatal-overnutrition on the detrimental impact of HFD-induced obesity on key elements of the adult GH-axis, which is conducted via mechanisms that are sexually-divergent.


Asunto(s)
Dieta Alta en Grasa , Hormona del Crecimiento/metabolismo , Obesidad/etiología , Hipernutrición/complicaciones , Caracteres Sexuales , Animales , Peso Corporal , Femenino , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Modelos Biológicos , Obesidad/genética , Especificidad de Órganos , Hipernutrición/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Wistar , Receptores de Somatotropina/genética , Receptores de Somatotropina/metabolismo
6.
Colorectal Dis ; 21(8): 903-908, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30963654

RESUMEN

AIM: Robotic techniques are being increasingly used in colorectal surgery. There is, however, a lack of training opportunities and structured training programmes. Robotic surgery has specific problems and challenges for trainers and trainees. Ergonomics, specific skills and user-machine interfaces are different from those in traditional laparoscopic surgery. The aim of this study was to establish expert consensus on the requirements for a robotic train-the-trainer curriculum amongst robotic surgeons and trainers. METHOD: This is a modified Delphi-type study involving 14 experts in robotic surgery teaching. A reiterating 19-item questionnaire was sent out to the same group and agreement levels analysed. A consensus of 0.8 or higher was considered to be high-level agreement. RESULTS: Response rates were 93-100% and most items reached high levels of agreement within three rounds. Specific requirements for a robotic faculty development curriculum included maximizing dual-console teaching, theatre team training, nontechnical skills training, patient safety, user-machine interface training and telementoring. CONCLUSION: A clear need for the development of a train-the-trainer curriculum has been identified. Further research is needed to assess feasibility, effectiveness and clinical impact of a robotic train-the-trainer curriculum.


Asunto(s)
Cirugía Colorrectal/educación , Curriculum/normas , Procedimientos Quirúrgicos Robotizados/educación , Formación del Profesorado/normas , Adulto , Consenso , Técnica Delphi , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
J Sports Sci ; 37(23): 2631-2638, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30893004

RESUMEN

This study's main objective is to analyse the relationship between network-based centrality measures and physical demands in elite football players. Thirty-six matches from La Liga, the Spanish league, were analysed in the 2017/18 season. The analysis of networks formed by team players passing the ball included: degree-prestige (DP), degree-centrality (DC), betweenness-centrality (BC), page-rank (PRP) and closeness-centrality (IRCC). A video-based system was used for analysing total distance (TDpos) and distance run >21Km/h (TD21pos) when the team was in possession of the ball. A magnitude-based inference and correlation analysis were applied. There were different styles of play, team-A was characterized by greater ball circulation (e.g. higher values of DP, DC, BC and IRCC) while team-B used a more direct game (lower values in centrality-metrics except with PRP). Furthermore, TDpos was higher in team-A than in team-B, but those differences disappeared for TD21pos between teams with the exception of the forwards. Finally, the correlation among centrality measures and physical performance were higher in team-B. Coaches could identify the key opponents and players who are linked to them, allowing to adjust performance strategies. Furthermore, interaction patterns between teammates can be used to identify preferential paths of cooperation and to take decisions regarding these relations in order to optimize team performance.


Asunto(s)
Rendimiento Atlético/fisiología , Destreza Motora/fisiología , Fútbol/fisiología , Procesos de Grupo , Humanos , Carrera/fisiología , Estudios de Tiempo y Movimiento
8.
Nat Commun ; 9(1): 4194, 2018 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305620

RESUMEN

Puberty is regulated by epigenetic mechanisms and is highly sensitive to metabolic and nutritional cues. However, the epigenetic pathways mediating the effects of nutrition and obesity on pubertal timing are unknown. Here, we identify Sirtuin 1 (SIRT1), a fuel-sensing deacetylase, as a molecule that restrains female puberty via epigenetic repression of the puberty-activating gene, Kiss1. SIRT1 is expressed in hypothalamic Kiss1 neurons and suppresses Kiss1 expression. SIRT1 interacts with the Polycomb silencing complex to decrease Kiss1 promoter activity. As puberty approaches, SIRT1 is evicted from the Kiss1 promoter facilitating a repressive-to-permissive switch in chromatin landscape. Early-onset overnutrition accelerates these changes, enhances Kiss1 expression and advances puberty. In contrast, undernutrition raises SIRT1 levels, protracts Kiss1 repression and delays puberty. This delay is mimicked by central pharmacological activation of SIRT1 or SIRT1 overexpression, achieved via transgenesis or virogenetic targeting to the ARC. Our results identify SIRT1-mediated inhibition of Kiss1 as key epigenetic mechanism by which nutritional cues and obesity influence mammalian puberty.


Asunto(s)
Epigénesis Genética , Kisspeptinas/genética , Fenómenos Fisiológicos de la Nutrición , Obesidad/metabolismo , Maduración Sexual , Sirtuina 1/metabolismo , Animales , Núcleo Arqueado del Hipotálamo/metabolismo , Cromatina/metabolismo , Femenino , Histonas/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Ratones Transgénicos , Modelos Biológicos , Neuronas/metabolismo , Estado Nutricional , Complejo Represivo Polycomb 2/metabolismo , Regiones Promotoras Genéticas , Ratas , Ratas Wistar , Factores de Tiempo
9.
Clin Transl Oncol ; 20(9): 1161-1167, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29374351

RESUMEN

PURPOSE: Increasing evidence shows that altered metabolism is a critical hallmark in colon cancer. There is a strong need to explore the molecular mechanisms underlying cancer metabolism. Whether the aberrant expression of microRNAs contributes to cancer metabolism is not fully understood. miR-328 is a putative potential target of SLC2A1, but the regulating mechanism between them remains unknown. We have examined whether miR-328 directly regulates SLC2A1/GLUT1 expression in colon cancer cells. METHODS: We performed in silico bioinformatic analyses to identify miR-328-mediated molecular pathways and targets. We also performed luciferase assays and western blot analyses in LOVO and SW480 colon cancer cell lines. In addition, we assessed miR-328 expression in 47 paired tumor and normal tissue specimens from resected colon cancer patients. RESULTS: Luciferase reporter assays showed that miR-328 directly targeted SLC2A1 3'-untranslated region (UTR), with a significant decrease in luciferase activity in both LOVO and SW480 cell lines. These results were validated by western blot. miR-328 expression was significantly downregulated in tumor tissue compared with paired normal tissue. CONCLUSIONS: Our results show that miR-328 targets SLC2A1/GLUT1. We suggest that miR-328 may be involved in the orchestration of the Warburg effect in colon cancer cells. Furthermore, miR-328 expression is reduced in colon cancer patients and thus inversely correlates with the classically reported upregulated SLC2A1/GLUT1 expression in tumors.


Asunto(s)
Neoplasias del Colon/metabolismo , Transportador de Glucosa de Tipo 1/genética , MicroARNs/fisiología , Regiones no Traducidas 3' , Anciano , Línea Celular Tumoral , Femenino , Transportador de Glucosa de Tipo 1/fisiología , Humanos , Masculino
10.
Heart ; 102(20): 1662-70, 2016 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-27296239

RESUMEN

OBJECTIVE: A safety threshold for baseline rhythm R-wave amplitudes during follow-up of implantable cardioverter defibrillators (ICD) has not been established. We aimed to analyse the amplitude distribution and undersensing rate during spontaneous episodes of ventricular fibrillation (VF), and define a safety amplitude threshold for baseline R-waves. METHODS: Data were obtained from an observational multicentre registry conducted at 48 centres in Spain. Baseline R-wave amplitudes and VF events were prospectively registered by remote monitoring. Signal processing algorithms were used to compare amplitudes of baseline R-waves with VF R-waves. All undersensed R-waves after the blanking period (120 ms) were manually marked. RESULTS: We studied 2507 patients from August 2011 to September 2014, which yielded 229 VF episodes (cycle length 189.6±29.1 ms) from 83 patients that were suitable for R-wave comparisons (follow-up 2.7±2.6 years). The majority (77.6%) of VF R-waves (n=13953) showed lower amplitudes than the reference baseline R-wave. The decrease in VF amplitude was progressively attenuated among subgroups of baseline R-wave amplitude (≥17; ≥12 to <17; ≥7 to <12; ≥2.2 to <7 mV) from the highest to the lowest: median deviations -51.2% to +22.4%, respectively (p=0.027). There were no significant differences in undersensing rates of VF R-waves among subgroups. Both the normalised histogram distribution and the undersensing risk function obtained from the ≥2.2 to <7 mV subgroup enabled the prediction that baseline R-wave amplitudes ≤2.5 mV (interquartile range: 2.3-2.8 mV) may lead to ≥25% of undersensed VF R-waves. CONCLUSIONS: Baseline R-wave amplitudes ≤2.5 mV during follow-up of patients with ICDs may lead to high risk of delayed detection of VF. TRIAL REGISTRATION NUMBER: NCT01561144; results.


Asunto(s)
Desfibriladores Implantables , Cardioversión Eléctrica/instrumentación , Sistema de Conducción Cardíaco/fisiopatología , Fibrilación Ventricular/terapia , Potenciales de Acción , Adulto , Anciano , Diagnóstico Tardío , Cardioversión Eléctrica/efectos adversos , Electrocardiografía/métodos , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Seguridad del Paciente , Valor Predictivo de las Pruebas , Diseño de Prótesis , Sistema de Registros , Tecnología de Sensores Remotos/métodos , Factores de Riesgo , Procesamiento de Señales Asistido por Computador , España , Telemetría/métodos , Factores de Tiempo , Resultado del Tratamiento , Fibrilación Ventricular/diagnóstico , Fibrilación Ventricular/fisiopatología
11.
Blood Cancer J ; 5: e352, 2015 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-26430723

RESUMEN

Acute myeloid leukemia (AML) is a heterogeneous disease whose prognosis is mainly related to the biological risk conferred by cytogenetics and molecular profiling. In elderly patients (⩾60 years) with normal karyotype AML miR-3151 have been identified as a prognostic factor. However, miR-3151 prognostic value has not been examined in younger AML patients. In the present work, we have studied miR-3151 alone and in combination with BAALC, its host gene, in a cohort of 181 younger intermediate-risk AML (IR-AML) patients. Patients with higher expression of miR-3151 had shorter overall survival (P=0.0025), shorter leukemia-free survival (P=0.026) and higher cumulative incidence of relapse (P=0.082). Moreover, in the multivariate analysis miR-3151 emerged as independent prognostic marker in both the overall series and within the unfavorable molecular prognostic category. Interestingly, the combined determination of both miR-3151 and BAALC improved this prognostic stratification, with patients with low levels of both parameters showing a better outcome compared with those patients harboring increased levels of one or both markers (P=0.003). In addition, we studied the microRNA expression profile associated with miR-3151 identifying a six-microRNA signature. In conclusion, the analysis of miR-3151 and BAALC expression may well contribute to an improved prognostic stratification of younger patients with IR-AML.


Asunto(s)
Biomarcadores de Tumor/genética , Leucemia Mieloide Aguda/genética , MicroARNs/genética , Proteínas de Neoplasias/genética , Adolescente , Adulto , Anciano , Análisis Citogenético , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Transcriptoma , Adulto Joven
12.
IEEE J Biomed Health Inform ; 19(4): 1253-63, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25823046

RESUMEN

The current development of cloud computing is completely changing the paradigm of data knowledge extraction in huge databases. An example of this technology in the cardiac arrhythmia field is the SCOOP platform, a national-level scientific cloud-based big data service for implantable cardioverter defibrillators. In this scenario, we here propose a new methodology for automatic classification of intracardiac electrograms (EGMs) in a cloud computing system, designed for minimal signal preprocessing. A new compression-based similarity measure (CSM) is created for low computational burden, so-called weighted fast compression distance, which provides better performance when compared with other CSMs in the literature. Using simple machine learning techniques, a set of 6848 EGMs extracted from SCOOP platform were classified into seven cardiac arrhythmia classes and one noise class, reaching near to 90% accuracy when previous patient arrhythmia information was available and 63% otherwise, hence overcoming in all cases the classification provided by the majority class. Results show that this methodology can be used as a high-quality service of cloud computing, providing support to physicians for improving the knowledge on patient diagnosis.


Asunto(s)
Arritmias Cardíacas/clasificación , Electrocardiografía/clasificación , Internet , Computación en Informática Médica , Arritmias Cardíacas/terapia , Bases de Datos Factuales , Desfibriladores Implantables , Humanos , Aprendizaje Automático , Sensibilidad y Especificidad
13.
Best Pract Res Clin Obstet Gynaecol ; 29(4): 554-64, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25770750

RESUMEN

Since the 1980s, minimally invasive techniques have been applied to an increasing number and variety of surgical procedures with a gradual increase in the complexity of procedures being successfully performed laparoscopically. In the past, obesity was considered a contraindication to laparoscopy due to the higher risk of co-morbid conditions such as diabetes, hypertension, coronary artery disease and venous thromboembolism. Performing laparoscopic gynaecological procedures in morbidly obese patients is no longer a rare phenomenon; however, it does necessitate changes in clinical practice patterns. Understanding of the physiological changes induced by laparoscopy, particularly in obese patients, is important so that these may be counteracted and adverse outcomes avoided. Laparoscopy in obese patients confers certain advantages such as shorter hospital stay, less post-operative pain and fewer wound infections. In addition to these benefits, minimal-access surgery has been demonstrated as safe and effective in obese patients; however, specific surgical strategies and operative techniques may need to be adopted.


Asunto(s)
Neoplasias de los Genitales Femeninos/cirugía , Procedimientos Quirúrgicos Ginecológicos/métodos , Laparoscopía/métodos , Obesidad Mórbida/complicaciones , Complicaciones Posoperatorias , Femenino , Enfermedades de los Genitales Femeninos/complicaciones , Enfermedades de los Genitales Femeninos/cirugía , Neoplasias de los Genitales Femeninos/complicaciones , Humanos , Tiempo de Internación , Obesidad/complicaciones , Dolor Postoperatorio , Posicionamiento del Paciente/métodos , Neumoperitoneo Artificial/métodos , Infección de la Herida Quirúrgica
15.
Rev Esp Cir Ortop Traumatol ; 59(1): 66-8, 2015.
Artículo en Español | MEDLINE | ID: mdl-24813623

RESUMEN

Radiocarpal dislocation is an extremely uncommon injury in Traumatology, and is usually produced by high energy trauma. There are two types of dislocation, type I: pure radiocarpal dislocation and type II: fracture-dislocation. The gold standard treatment according to the literature is surgical treatment fixing the fractures and repairing the injured ligaments. We report a clinical case of radiocarpal dislocation type I in a healthy 19 year-old male after a minor trauma. The dislocation was reduced by traction, and the wrist immobilized in a plaster cast. The functional outcome 12 months after the injury was excellent.


Asunto(s)
Luxaciones Articulares/etiología , Traumatismos de la Muñeca/etiología , Articulación de la Muñeca , Moldes Quirúrgicos , Humanos , Luxaciones Articulares/diagnóstico , Luxaciones Articulares/terapia , Masculino , Tracción , Traumatismos de la Muñeca/diagnóstico , Traumatismos de la Muñeca/terapia , Adulto Joven
16.
Cell Death Dis ; 5: e1573, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25522267

RESUMEN

Mitochondrial alterations are critically involved in increased vulnerability to disease during aging. We investigated the contribution of mitochondria-sarcoplasmic reticulum (SR) communication in cardiomyocyte functional alterations during aging. Heart function (echocardiography) and ATP/phosphocreatine (NMR spectroscopy) were preserved in hearts from old mice (>20 months) with respect to young mice (5-6 months). Mitochondrial membrane potential and resting O2 consumption were similar in mitochondria from young and old hearts. However, maximal ADP-stimulated O2 consumption was specifically reduced in interfibrillar mitochondria from aged hearts. Second generation proteomics disclosed an increased mitochondrial protein oxidation in advanced age. Because energy production and oxidative status are regulated by mitochondrial Ca2+, we investigated the effect of age on mitochondrial Ca2+ uptake. Although no age-dependent differences were found in Ca2+ uptake kinetics in isolated mitochondria, mitochondrial Ca2+ uptake secondary to SR Ca2+ release was significantly reduced in cardiomyocytes from old hearts, and this effect was associated with decreased NAD(P)H regeneration and increased mitochondrial ROS upon increased contractile activity. Immunofluorescence and proximity ligation assay identified the defective communication between mitochondrial voltage-dependent anion channel and SR ryanodine receptor (RyR) in cardiomyocytes from aged hearts associated with altered Ca2+ handling. Age-dependent alterations in SR Ca2+ transfer to mitochondria and in Ca2+ handling could be reproduced in cardiomyoctes from young hearts after interorganelle disruption with colchicine, at concentrations that had no effect in aged cardiomyocytes or isolated mitochondria. Thus, defective SR-mitochondria communication underlies inefficient interorganelle Ca2+ exchange that contributes to energy demand/supply mistmach and oxidative stress in the aged heart.


Asunto(s)
Envejecimiento/metabolismo , Calcio/metabolismo , Mitocondrias Cardíacas/metabolismo , Miocardio/metabolismo , Retículo Sarcoplasmático/metabolismo , Adenosina Difosfato/metabolismo , Animales , Transporte Biológico , Femenino , Corazón/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Contracción Miocárdica , Oxidación-Reducción , Oxígeno/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Canales Aniónicos Dependientes del Voltaje/metabolismo
17.
Endocrinology ; 154(9): 3387-400, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23751873

RESUMEN

Body energy stores and metabolic cues influence the onset of puberty. However, the pubertal impact of early nutritional challenges has been only fragmentarily addressed. We evaluated here the consequences, in terms of pubertal timing and hormonal markers, of various nutritional manipulations during pre- or postnatal maturation in rats of both sexes. Males and females were submitted to gestational undernutrition (UNG) or peripubertal (SUB) subnutrition or were raised in large (LL; underfeeding) or small (SL; overfeeding) litters. In addition, groups of UNG, LL, and SL rats were fed on a high-fat diet (HFD) after weaning. Postnatal overfeeding resulted in higher body weights (BWs) during pubertal transition in both sexes, but only SL males displayed overtly advanced external signs of puberty. Postnatal underfeeding persistently decreased BW gain during puberty, yet the magnitude of pubertal delay was greater in LL males. In contrast, regardless of postnatal nutrition, HFD tended to advance the onset of puberty in females but did not alter pubertal timing in males. Likewise, SUB females displayed a marked delay in BW gain and puberty onset, whereas despite similar reduction in BW, SUB males showed normal timing of puberty. These sex divergences were also detected in various hormonal and metabolic indices so that postnatal overnutrition consistently increased LH, FSH, leptin, and insulin levels only in pubertal females, whereas HFD decreased gonadotropin levels in SL females but increased them in SL males. Notably, UNG rats did not show signs of delayed puberty but displayed a striking sex dimorphism in serum insulin/glucose levels, regardless of the diet, so that only UNG males had signs of presumable insulin resistance. Our data disclose important sex differences in the impact of various early nutritional challenges on the timing of puberty, which may help to explain the different trends of altered puberty and related comorbidities between sexes.


Asunto(s)
Desarrollo Fetal , Trastornos Gonadales/etiología , Lactancia , Desnutrición/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos , Hipernutrición/fisiopatología , Maduración Sexual , Factores de Edad , Animales , Biomarcadores/sangre , Peso Corporal , Dieta Alta en Grasa/efectos adversos , Femenino , Trastornos Gonadales/sangre , Gonadotropinas/sangre , Resistencia a la Insulina , Masculino , Embarazo , Ratas , Ratas Wistar , Caracteres Sexuales
18.
Atherosclerosis ; 227(1): 79-88, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23312784

RESUMEN

Sterol regulatory element-binding proteins (SREBPs) negatively modulate the expression of the CD91/low-density lipoprotein receptor-related protein (LRP1), a carrier and signaling receptor that mediates the endocytosis of more than 40 structurally and functionally distinct ligands. The aim of this work was to analyze whether lipopolysaccharide (LPS) can regulate LRP1 expression through SREBPs in human monocyte-derived macrophages (HMDM). LPS led to LRP1 mRNA and protein inhibition in a dose- and time-dependent manner. Concomitantly, a strong upregulation of SREBP-1 mRNA and SREBP-1 nuclear protein levels was observed in LPS-treated HMDM. The specific silencing of SREBP-1 efficiently prevented LRP1 reduction caused by LPS. SREBP-1 mRNA and nuclear protein levels remained high in HMDM treated with LPS unexposed or exposed to LDL. Native (nLDL) or aggregated LDL (agLDL) per se downregulated SREBP-2 expression levels and increased LRP1 expression. However, lipoproteins did not significantly alter the effect of LPS on SREBP-1 and LRP1 expression. Collectively, these data support that lipoproteins and LPS exert their modulatory effect on LRP1 expression through different SREBP isoforms, SREBP-2 and SREBP-1, respectively. These results highlight a crucial role of SREBP-1 as a mediator of the downregulatory effects of LPS on LRP1 expression in human macrophages, independently of the absence or presence of modified lipoproteins.


Asunto(s)
Lipopolisacáridos/farmacología , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/biosíntesis , Macrófagos/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles/genética , Regulación hacia Abajo , Humanos , Macrófagos/efectos de los fármacos , Proteínas Nucleares/metabolismo , ARN Mensajero/metabolismo
19.
Bone Marrow Transplant ; 48(3): 396-402, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22858507

RESUMEN

The potential impact on patient outcome of different Minimal residual disease (MRD) levels at time of transplant in patients with lymphoblastic leukemia undergoing allogeneic hematopoietic SCT (HSCT) remains uncertain. In this study, we quantified MRD levels at time of transplant using multiparameter flow cytometry (MFC). Mononuclear cells from marrow aspirates were obtained from 102 adult and child patients before their conditioning regimen. Quantification of MRD levels was carried out by detecting patient-specific leukemia-associated immunophenotypes using four-color MFC. Thirty patients exhibited measurable levels of MRD at the time of transplant, with low levels (0.01 to 0.1%) in 12 cases, intermediate levels (>0.1 to 1%) in 8 cases and high levels (>1%) in 10 cases. The leukemia-free survival (LFS) rates were 65.9±7.0%, 42.9±15.7% and 0% for negative, low levels 0.1% and intermediate-high levels >0.1%, respectively (P<0.001, log-rank test). Overall survival (OS) was 52.3±7.6%, 28.6±13.8% and 0% for MRD-negative, low levels 0.1% and intermediate-high levels >0.1%, respectively (P<0.001, log-rank test). Multivariate Cox analysis confirmed that detection of leukemia cells by flow cytometry at transplant was the most significantly adverse factor for OS, LFS and EFS after transplant.


Asunto(s)
Citometría de Flujo/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirugía , Adolescente , Niño , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasia Residual , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Trasplante Homólogo , Resultado del Tratamiento
20.
Endocrinology ; 153(4): 1959-71, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22334726

RESUMEN

Nesfatin-1, product of the precursor NEFA/nucleobindin2 (NUCB2), was initially identified as anorectic hypothalamic neuropeptide, acting in a leptin-independent manner. In addition to its central role in the control of energy homeostasis, evidence has mounted recently that nesfatin-1 is also produced in peripheral metabolic tissues, such as pancreas, adipose, and gut. Moreover, nesfatin-1 has been shown to participate in the control of body functions gated by whole-body energy homeostasis, including puberty onset. Yet, whether, as is the case for other metabolic neuropeptides, NUCB2/nesfatin-1 participates in the direct control of gonadal function remains unexplored. We document here for the first time the expression of NUCB2 mRNA in rat, mouse, and human testes, where NUCB2/nesfatin-1 protein was identified in interstitial mature Leydig cells. Yet in rats, NUCB2/nesfatin-1 became expressed in Sertoli cells upon Leydig cell elimination and was also detected in Leydig cell progenitors. Although NUCB2 mRNA levels did not overtly change in rat testis during pubertal maturation and after short-term fasting, NUCB2/nesfatin-1 content significantly increased along the puberty-to-adult transition and was markedly suppressed after fasting. In addition, testicular NUCB2/nesfatin-1 expression was up-regulated by pituitary LH, because hypophysectomy decreased, whereas human choriogonadotropin (super-agonist of LH receptors) replacement enhanced, NUCB2/nesfatin-1 mRNA and peptide levels. Finally, nesfatin-1 increased human choriogonadotropin-stimulated testosterone secretion by rat testicular explants ex vivo. Our data are the first to disclose the presence and functional role of NUCB2/nesfatin-1 in the testis, where its expression is regulated by developmental, metabolic, and hormonal cues as well as by Leydig cell-derived factors. Our observations expand the reproductive dimension of nesfatin-1, which may operate directly at the testicular level to link energy homeostasis, puberty onset, and gonadal function.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al ADN/metabolismo , Metabolismo Energético/fisiología , Proteínas del Tejido Nervioso/metabolismo , Maduración Sexual/fisiología , Testículo/metabolismo , Envejecimiento/metabolismo , Animales , Regulación de la Expresión Génica , Humanos , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Nucleobindinas , Ratas , Ratas Wistar , Testículo/citología , Testículo/crecimiento & desarrollo , Testosterona/metabolismo
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