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1.
Cell ; 153(5): 1064-79, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23706743

RESUMEN

Metabolic adaptation is essential for cell survival during nutrient deprivation. We report that eukaryotic elongation factor 2 kinase (eEF2K), which is activated by AMP-kinase (AMPK), confers cell survival under acute nutrient depletion by blocking translation elongation. Tumor cells exploit this pathway to adapt to nutrient deprivation by reactivating the AMPK-eEF2K axis. Adaptation of transformed cells to nutrient withdrawal is severely compromised in cells lacking eEF2K. Moreover, eEF2K knockdown restored sensitivity to acute nutrient deprivation in highly resistant human tumor cell lines. In vivo, overexpression of eEF2K rendered murine tumors remarkably resistant to caloric restriction. Expression of eEF2K strongly correlated with overall survival in human medulloblastoma and glioblastoma multiforme. Finally, C. elegans strains deficient in efk-1, the eEF2K ortholog, were severely compromised in their response to nutrient depletion. Our data highlight a conserved role for eEF2K in protecting cells from nutrient deprivation and in conferring tumor cell adaptation to metabolic stress. PAPERCLIP:


Asunto(s)
Caenorhabditis elegans/metabolismo , Quinasa del Factor 2 de Elongación/metabolismo , Neoplasias/fisiopatología , Extensión de la Cadena Peptídica de Translación , Transducción de Señal , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Neoplasias Encefálicas/fisiopatología , Caenorhabditis elegans/genética , Supervivencia Celular , Transformación Celular Neoplásica , Quinasa del Factor 2 de Elongación/genética , Privación de Alimentos , Glioblastoma/fisiopatología , Células HeLa , Humanos , Ratones , Ratones Desnudos , Células 3T3 NIH , Trasplante de Neoplasias , Factor 2 de Elongación Peptídica/metabolismo , Trasplante Heterólogo
2.
Annu Rev Pharmacol Toxicol ; 64: 455-479, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-37738504

RESUMEN

Proteogenomics refers to the integration of comprehensive genomic, transcriptomic, and proteomic measurements from the same samples with the goal of fully understanding the regulatory processes converting genotypes to phenotypes, often with an emphasis on gaining a deeper understanding of disease processes. Although specific genetic mutations have long been known to drive the development of multiple cancers, gene mutations alone do not always predict prognosis or response to targeted therapy. The benefit of proteogenomics research is that information obtained from proteins and their corresponding pathways provides insight into therapeutic targets that can complement genomic information by providing an additional dimension regarding the underlying mechanisms and pathophysiology of tumors. This review describes the novel insights into tumor biology and drug resistance derived from proteogenomic analysis while highlighting the clinical potential of proteogenomic observations and advances in technique and analysis tools.


Asunto(s)
Medicina de Precisión , Proteogenómica , Humanos , Proteómica , Genómica , Espectrometría de Masas
3.
Nature ; 600(7890): 737-742, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34880491

RESUMEN

Stability of the epigenetic landscape underpins maintenance of the cell-type-specific transcriptional profile. As one of the main repressive epigenetic systems, DNA methylation has been shown to be important for long-term gene silencing; its loss leads to ectopic and aberrant transcription in differentiated cells and cancer1. The developing mouse germ line endures global changes in DNA methylation in the absence of widespread transcriptional activation. Here, using an ultra-low-input native chromatin immunoprecipitation approach, we show that following DNA demethylation the gonadal primordial germ cells undergo remodelling of repressive histone modifications, resulting in a sex-specific signature in mice. We further demonstrate that Polycomb has a central role in transcriptional control in the newly hypomethylated germline genome as the genetic loss of Ezh2 leads to aberrant transcriptional activation, retrotransposon derepression and dramatic loss of developing female germ cells. This sex-specific effect of Ezh2 deletion is explained by the distinct landscape of repressive modifications observed in male and female germ cells. Overall, our study provides insight into the dynamic interplay between repressive chromatin modifications in the context of a developmental reprogramming system.


Asunto(s)
Ensamble y Desensamble de Cromatina , Células Germinativas , Animales , Cromatina/genética , Cromatina/metabolismo , Inmunoprecipitación de Cromatina , Metilación de ADN , Epigénesis Genética , Femenino , Células Germinativas/metabolismo , Masculino , Ratones , Proteínas del Grupo Polycomb/metabolismo
4.
Circ Res ; 132(9): e116-e133, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-36927079

RESUMEN

BACKGROUND: Small-conductance Ca2+-activated K+ (SK)-channel inhibitors have antiarrhythmic effects in animal models of atrial fibrillation (AF), presenting a potential novel antiarrhythmic option. However, the regulation of SK-channels in human atrial cardiomyocytes and its modification in patients with AF are poorly understood and were the object of this study. METHODS: Apamin-sensitive SK-channel current (ISK) and action potentials were recorded in human right-atrial cardiomyocytes from sinus rhythm control (Ctl) patients or patients with (long-standing persistent) chronic AF (cAF). RESULTS: ISK was significantly higher, and apamin caused larger action potential prolongation in cAF- versus Ctl-cardiomyocytes. Sensitivity analyses in an in silico human atrial cardiomyocyte model identified IK1 and ISK as major regulators of repolarization. Increased ISK in cAF was not associated with increases in mRNA/protein levels of SK-channel subunits in either right- or left-atrial tissue homogenates or right-atrial cardiomyocytes, but the abundance of SK2 at the sarcolemma was larger in cAF versus Ctl in both tissue-slices and cardiomyocytes. Latrunculin-A and primaquine (anterograde and retrograde protein-trafficking inhibitors) eliminated the differences in SK2 membrane levels and ISK between Ctl- and cAF-cardiomyocytes. In addition, the phosphatase-inhibitor okadaic acid reduced ISK amplitude and abolished the difference between Ctl- and cAF-cardiomyocytes, indicating that reduced calmodulin-Thr80 phosphorylation due to increased protein phosphatase-2A levels in the SK-channel complex likely contribute to the greater ISK in cAF-cardiomyocytes. Finally, rapid electrical activation (5 Hz, 10 minutes) of Ctl-cardiomyocytes promoted SK2 membrane-localization, increased ISK and reduced action potential duration, effects greatly attenuated by apamin. Latrunculin-A or primaquine prevented the 5-Hz-induced ISK-upregulation. CONCLUSIONS: ISK is upregulated in patients with cAF due to enhanced channel function, mediated by phosphatase-2A-dependent calmodulin-Thr80 dephosphorylation and tachycardia-dependent enhanced trafficking and targeting of SK-channel subunits to the sarcolemma. The observed AF-associated increases in ISK, which promote reentry-stabilizing action potential duration shortening, suggest an important role for SK-channels in AF auto-promotion and provide a rationale for pursuing the antiarrhythmic effects of SK-channel inhibition in humans.


Asunto(s)
Fibrilación Atrial , Animales , Humanos , Fibrilación Atrial/metabolismo , Apamina/metabolismo , Apamina/farmacología , Primaquina/metabolismo , Primaquina/farmacología , Calmodulina/metabolismo , Atrios Cardíacos/metabolismo , Miocitos Cardíacos/metabolismo , Antiarrítmicos/uso terapéutico , Potenciales de Acción/fisiología , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/metabolismo
5.
Annu Rev Psychol ; 75: 495-526, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-37585666

RESUMEN

Research in cultural psychology over the last three decades has revealed the profound influence of culture on cognitive, emotional, and motivational processes shaping individuals into active agents. This article aims to show cultural psychology's promise in three key steps. First, we review four notable cultural dimensions believed to underlie cultural variations: independent versus interdependent self, individualism versus collectivism, tightness versus looseness of social norms, and relational mobility. Second, we examine how ecology and geography shape human activities and give rise to organized systems of cultural practices and meanings, called eco-cultural complexes. In turn, the eco-cultural complex of each zone is instrumental in shaping a wide range of psychological processes, revealing a psychological diversity that extends beyond the scope of the current East-West literature. Finally, we examine some of the non-Western cultural zones present today, including Arab, East Asian, Latin American, and South Asian zones, and discuss how they may have contributed, to varying degrees, to the formation of the contemporary Western cultural zone.


Asunto(s)
Emociones , Motivación , Humanos , Normas Sociales
6.
Anal Chem ; 96(1): 364-372, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38156894

RESUMEN

We have developed a statistical model-based approach to the quality analysis (QA) and quality control (QC) of a gas micro pre-concentrator chip (µPC) performance when manufactured at scale for chemical and biochemical analysis of volatile organic compounds (VOCs). To test the proposed model, a medium-sized university-led production batch of 30 wafers of chips were subjected to rigorous chemical performance testing. We quantitatively report the outcomes of each manufacturing process step leading to the final functional chemical sensor chip. We implemented a principal component analysis (PCA) model to score individual chip chemical performance, and we observed that the first two principal components represent 74.28% of chemical testing variance with 111 of 118 viable chips falling into the 95% confidence interval. Chemical performance scores and chip manufacturing data were analyzed using a multivariate regression model to determine the most influential manufacturing parameters and steps. In our analysis, we find the amount of sorbent mass present in the chip (variable importance score = 2.6) and heater and the RTD resistance values (variable importance score = 1.1) to be the manufacturing parameters with the greatest impact on chemical performance. Other non-obvious latent manufacturing parameters also had quantified influence. Statistical distributions for each manufacturing step will allow future large-scale production runs to be statistically sampled during production to perform QA/QC in a real-time environment. We report this study as the first data-driven, model-based production of a microfabricated chemical sensor.

7.
PLoS Pathog ; 18(5): e1010518, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35584193

RESUMEN

The three human pathogenic ebolaviruses: Zaire (EBOV), Bundibugyo (BDBV), and Sudan (SUDV) virus, cause severe disease with high fatality rates. Epitopes of ebolavirus glycoprotein (GP) recognized by antibodies with binding breadth for all three ebolaviruses are of major interest for rational vaccine design. In particular, the heptad repeat 2 -membrane-proximal external region (HR2-MPER) epitope is relatively conserved between EBOV, BDBV, and SUDV GP and targeted by human broadly-neutralizing antibodies. To study whether this epitope can serve as an immunogen for the elicitation of broadly-reactive antibody responses, protein design in Rosetta was employed to transplant the HR2-MPER epitope identified from a co-crystal structure with the known broadly-reactive monoclonal antibody (mAb) BDBV223 onto smaller scaffold proteins. From computational analysis, selected immunogen designs were produced as recombinant proteins and functionally validated, leading to the identification of a sterile alpha motif (SAM) domain displaying the BDBV-HR2-MPER epitope near its C terminus as a promising candidate. The immunogen was fused to one component of a self-assembling, two-component nanoparticle and tested for immunogenicity in rabbits. Robust titers of cross-reactive serum antibodies to BDBV and EBOV GPs and moderate titers to SUDV GP were induced following immunization. To confirm the structural composition of the immunogens, solution NMR studies were conducted and revealed structural flexibility in the C-terminal residues of the epitope. Overall, our study represents the first report on an epitope-focused immunogen design based on the structurally challenging BDBV-HR2-MPER epitope.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , Glicoproteínas , Conejos
8.
Circ Res ; 130(7): 994-1010, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35193397

RESUMEN

RATIONALE: Atrial fibrillation (AF) and heart failure often coexist, but their interaction is poorly understood. Clinical data indicate that the arrhythmic component of AF may contribute to left ventricular (LV) dysfunction. OBJECTIVE: This study investigates the effects and molecular mechanisms of AF on the human LV. METHODS AND RESULTS: Ventricular myocardium from patients with aortic stenosis and preserved LV function with sinus rhythm or rate-controlled AF was studied. LV myocardium from patients with sinus rhythm and patients with AF showed no differences in fibrosis. In functional studies, systolic Ca2+ transient amplitude of LV cardiomyocytes was reduced in patients with AF, while diastolic Ca2+ levels and Ca2+ transient kinetics were not statistically different. These results were confirmed in LV cardiomyocytes from nonfailing donors with sinus rhythm or AF. Moreover, normofrequent AF was simulated in vitro using arrhythmic or rhythmic pacing (both at 60 bpm). After 24 hours of AF-simulation, human LV cardiomyocytes from nonfailing donors showed an impaired Ca2+ transient amplitude. For a standardized investigation of AF-simulation, human iPSC-cardiomyocytes were tested. Seven days of AF-simulation caused reduced systolic Ca2+ transient amplitude and sarcoplasmic reticulum Ca2+ load likely because of an increased diastolic sarcoplasmic reticulum Ca2+ leak. Moreover, cytosolic Na+ concentration was elevated and action potential duration was prolonged after AF-simulation. We detected an increased late Na+ current as a potential trigger for the detrimentally altered Ca2+/Na+-interplay. Mechanistically, reactive oxygen species were higher in the LV of patients with AF. CaMKII (Ca2+/calmodulin-dependent protein kinase IIδc) was found to be more oxidized at Met281/282 in the LV of patients with AF leading to an increased CaMKII activity and consequent increased RyR2 phosphorylation. CaMKII inhibition and ROS scavenging ameliorated impaired systolic Ca2+ handling after AF-simulation. CONCLUSIONS: AF causes distinct functional and molecular remodeling of the human LV. This translational study provides the first mechanistic characterization and the potential negative impact of AF in the absence of tachycardia on the human ventricle.


Asunto(s)
Fibrilación Atrial , Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Humanos , Miocitos Cardíacos/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo
9.
Med Mycol ; 62(7)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38744661

RESUMEN

The second international meeting on endemic mycoses of the Americas (IMEMA) and the first international symposium on implantation mycoses (ISIM) took place in Santiago del Estero, Argentina, on September 25-27, 2023. The conference provided a platform for researchers, clinicians, and experts to discuss the latest developments in the field of endemic and implantation mycoses. Topics included epidemiology, diagnostic advances, treatment strategies, and the impact of environmental factors on the spread of these fungal diseases. IMEMA and ISIM contributed to the regional discourse on the mycoses, emphasizing the importance of international cooperation in addressing these public health challenges.


IMEMA/ISIM, held in Santiago del Estero, Argentina, convened experts to discuss endemic and implantation mycoses, covering topics such as epidemiology, diagnostics, treatment, and advocacy. The event highlighted ongoing efforts in combating these diseases.


Asunto(s)
Enfermedades Endémicas , Micosis , Humanos , Micosis/epidemiología , Micosis/microbiología , Américas/epidemiología , Argentina/epidemiología , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/epidemiología
10.
Cell ; 138(6): 1083-95, 2009 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-19766563

RESUMEN

Stem-like cells may be integral to the development and maintenance of human cancers. Direct proof is still lacking, mainly because of our poor understanding of the biological differences between normal and cancer stem cells (SCs). Using the ErbB2 transgenic model of breast cancer, we found that self-renewing divisions of cancer SCs are more frequent than their normal counterparts, unlimited and symmetric, thus contributing to increasing numbers of SCs in tumoral tissues. SCs with targeted mutation of the tumor suppressor p53 possess the same self-renewal properties as cancer SCs, and their number increases progressively in the p53 null premalignant mammary gland. Pharmacological reactivation of p53 correlates with restoration of asymmetric divisions in cancer SCs and tumor growth reduction, without significant effects on additional cancer cells. These data demonstrate that p53 regulates polarity of cell division in mammary SCs and suggest that loss of p53 favors symmetric divisions of cancer SCs, contributing to tumor growth.


Asunto(s)
División Celular , Neoplasias Mamarias Animales/metabolismo , Células Madre Neoplásicas/citología , Proteína p53 Supresora de Tumor/metabolismo , Animales , Polaridad Celular , Femenino , Humanos , Ratones , Ratones Transgénicos , Células Madre Neoplásicas/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
11.
Nature ; 555(7696): 392-396, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29513657

RESUMEN

Gametes are highly specialized cells that can give rise to the next generation through their ability to generate a totipotent zygote. In mice, germ cells are first specified in the developing embryo around embryonic day (E) 6.25 as primordial germ cells (PGCs). Following subsequent migration into the developing gonad, PGCs undergo a wave of extensive epigenetic reprogramming around E10.5-E11.5, including genome-wide loss of 5-methylcytosine. The underlying molecular mechanisms of this process have remained unclear, leading to our inability to recapitulate this step of germline development in vitro. Here we show, using an integrative approach, that this complex reprogramming process involves coordinated interplay among promoter sequence characteristics, DNA (de)methylation, the polycomb (PRC1) complex and both DNA demethylation-dependent and -independent functions of TET1 to enable the activation of a critical set of germline reprogramming-responsive genes involved in gamete generation and meiosis. Our results also reveal an unexpected role for TET1 in maintaining but not driving DNA demethylation in gonadal PGCs. Collectively, our work uncovers a fundamental biological role for gonadal germline reprogramming and identifies the epigenetic principles of the PGC-to-gonocyte transition that will help to guide attempts to recapitulate complete gametogenesis in vitro.


Asunto(s)
Reprogramación Celular/genética , Epigénesis Genética , Gametogénesis/genética , Células Germinativas/citología , Células Germinativas/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animales , Metilación de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Masculino , Meiosis , Ratones , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo
12.
Eur Arch Psychiatry Clin Neurosci ; 274(6): 1265-1276, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38551773

RESUMEN

Exercise interventions are nowadays considered as effective add-on treatments in people with schizophrenia but are usually associated with high dropout rates. Therefore, the present study investigated potential predictors of adherence from a large multicenter study, encompassing two types of exercise training, conducted over a 6-month period with individuals with schizophrenia. First, we examined the role of multiple participants' characteristics, including levels of functioning, symptom severity, cognitive performance, quality of life, and physical fitness. Second, we used K-means clustering to identify clinical subgroups of participants that potentially exhibited superior adherence. Last, we explored if adherence could be predicted on the individual level using Random Forest, Logistic Regression, and Ridge Regression. We found that individuals with higher levels of functioning at baseline were more likely to adhere to the exercise interventions, while other factors such as symptom severity, cognitive performance, quality of life or physical fitness seemed to be less influential. Accordingly, the high-functioning group with low symptoms exhibited a greater likelihood of adhering to the interventions compared to the severely ill group. Despite incorporating various algorithms, it was not possible to predict adherence at the individual level. These findings add to the understanding of the factors that influence adherence to exercise interventions. They underscore the predictive importance of daily life functioning while indicating a lack of association between symptom severity and adherence. Future research should focus on developing targeted strategies to improve adherence, particularly for people with schizophrenia who suffer from impairments in daily functioning.Clinical trials registration The study of this manuscript which the manuscript is based was registered in the International Clinical Trials Database, ClinicalTrials.gov (NCT number: NCT03466112, https://clinicaltrials.gov/ct2/show/NCT03466112?term=NCT03466112&draw=2&rank=1 ) and in the German Clinical Trials Register (DRKS-ID: DRKS00009804.


Asunto(s)
Terapia por Ejercicio , Cooperación del Paciente , Esquizofrenia , Humanos , Esquizofrenia/terapia , Esquizofrenia/rehabilitación , Esquizofrenia/fisiopatología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Cooperación del Paciente/estadística & datos numéricos , Calidad de Vida , Aptitud Física/fisiología
13.
Nature ; 562(7728): 526-531, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30333627

RESUMEN

The implementation of targeted therapies for acute myeloid leukaemia (AML) has been challenging because of the complex mutational patterns within and across patients as well as a dearth of pharmacologic agents for most mutational events. Here we report initial findings from the Beat AML programme on a cohort of 672 tumour specimens collected from 562 patients. We assessed these specimens using whole-exome sequencing, RNA sequencing and analyses of ex vivo drug sensitivity. Our data reveal mutational events that have not previously been detected in AML. We show that the response to drugs is associated with mutational status, including instances of drug sensitivity that are specific to combinatorial mutational events. Integration with RNA sequencing also revealed gene expression signatures, which predict a role for specific gene networks in the drug response. Collectively, we have generated a dataset-accessible through the Beat AML data viewer (Vizome)-that can be leveraged to address clinical, genomic, transcriptomic and functional analyses of the biology of AML.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Genoma Humano/genética , Genómica , Leucemia Mieloide Aguda/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , ADN (Citosina-5-)-Metiltransferasas/genética , ADN Metiltransferasa 3A , Conjuntos de Datos como Asunto , Exoma/genética , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Terapia Molecular Dirigida , Proteínas Nucleares/genética , Nucleofosmina , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genética , Análisis de Secuencia de ARN , Factores de Empalme Serina-Arginina/genética
14.
Phytopathology ; 114(1): 84-92, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37486097

RESUMEN

Citrus greening disease, or Huanglongbing (HLB), has devastated citrus crops globally in recent years. The causal bacterium, 'Candidatus Liberibacter asiaticus', presents a sampling issue for qPCR diagnostics and results in a high false negative rate. In this work, we compared six metabolomics assays to identify HLB-infected citrus trees from leaf tissue extracted from 30 control and 30 HLB-infected trees. A liquid chromatography-mass spectrometry-based assay was most accurate. A final partial least squares-discriminant analysis (PLS-DA) model was trained and validated on 690 leaf samples with corresponding qPCR measures from three citrus varieties (Rio Red grapefruit, Hamlin sweet orange, and Valencia sweet orange) from orchards in Florida and Texas. Trees were naturally infected with HLB transmitted by the insect vector Diaphorina citri. In a randomized validation set, the assay was 99.9% accurate to classify diseased from nondiseased samples. This model was applied to samples from trees receiving plant defense-inducer compounds or biological treatments to prevent or cure HLB infection. From two trials, HLB-related metabolite abundances and PLS-DA scores were tracked longitudinally and compared with those of control trees. We demonstrate how our assay can assess tree health and the efficacy of HLB treatments and conclude that no trialed treatment was efficacious.


Asunto(s)
Citrus sinensis , Citrus , Hemípteros , Liberibacter , Rhizobiaceae , Citrus/microbiología , Rhizobiaceae/genética , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , Árboles
15.
Eur Heart J ; 44(27): 2483-2494, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-36810794

RESUMEN

AIMS: Atrial fibrillation (AF) is associated with altered cAMP/PKA signaling and an AF-promoting reduction of L-type Ca2+-current (ICa,L), the mechanisms of which are poorly understood. Cyclic-nucleotide phosphodiesterases (PDEs) degrade cAMP and regulate PKA-dependent phosphorylation of key calcium-handling proteins, including the ICa,L-carrying Cav1.2α1C subunit. The aim was to assess whether altered function of PDE type-8 (PDE8) isoforms contributes to the reduction of ICa,L in persistent (chronic) AF (cAF) patients. METHODS AND RESULTS: mRNA, protein levels, and localization of PDE8A and PDE8B isoforms were measured by RT-qPCR, western blot, co-immunoprecipitation and immunofluorescence. PDE8 function was assessed by FRET, patch-clamp and sharp-electrode recordings. PDE8A gene and protein levels were higher in paroxysmal AF (pAF) vs. sinus rhythm (SR) patients, whereas PDE8B was upregulated in cAF only. Cytosolic abundance of PDE8A was higher in atrial pAF myocytes, whereas PDE8B tended to be more abundant at the plasmalemma in cAF myocytes. In co-immunoprecipitation, only PDE8B2 showed binding to Cav1.2α1C subunit which was strongly increased in cAF. Accordingly, Cav1.2α1C showed a lower phosphorylation at Ser1928 in association with decreased ICa,L in cAF. Selective PDE8 inhibition increased Ser1928 phosphorylation of Cav1.2α1C, enhanced cAMP at the subsarcolemma and rescued the lower ICa,L in cAF, which was accompanied by a prolongation of action potential duration at 50% of repolarization. CONCLUSION: Both PDE8A and PDE8B are expressed in human heart. Upregulation of PDE8B isoforms in cAF reduces ICa,L via direct interaction of PDE8B2 with the Cav1.2α1C subunit. Thus, upregulated PDE8B2 might serve as a novel molecular mechanism of the proarrhythmic reduction of ICa,L in cAF.


Asunto(s)
Fibrilación Atrial , Humanos , Calcio/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Miocitos Cardíacos/fisiología , Fosforilación
16.
Women Health ; 64(2): 165-174, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38229419

RESUMEN

This longitudinal study aimed to analyze the influence of physical activity (PA) on the relationship between body adiposity and cardiac autonomic modulation (CAM) in women survivors of breast cancer. We collected body adiposity through electrical bioimpedance considering body fat percentage (BFP), CAM through heart rate variability (considering RMSSD, SDNN, PNN50, LF (m2), HF (m2), SD1 indexes and SD1/SD2 ratio) and PA through a questionnaire in 64 participants (58.0 ± 9.6 years), recruited through the local association of support for breast cancer and by direct indications from city mastologists. After insertion of PA into the multivariate statistical model, significant attenuation was observed in the relationship between body adiposity and CAM for the indices: SDNN (ß = -0.94; 95 percent CI: -1.93; 0.04; p = .060) and SD1/SD2 (ß = -0.01;95 percent CI = -0.02; 0.001; p = .065). In conclusion, it was observed that PA was able to mitigate the relationships between BFP and CAM (considering SDNN index and SD1/SD2 ratio) in breast cancer survivors.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Sindactilia , Humanos , Femenino , Adiposidad , Estudios Longitudinales , Obesidad , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología
17.
Molecules ; 29(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38930987

RESUMEN

Peanut shells' adsorption performance in caffeine and triclosan removal was studied. Peanut shells were analyzed for their chemical composition, morphology, and surface functional groups. Batch adsorption and fixed-bed column experiments were carried out with solutions containing 30 mg/L of caffeine and triclosan. The parameters examined included peanut shell particle size (120-150, 300-600, and 800-2000 µm), adsorbent dose (0.02-60 g/L), contact time (up to 180 min), bed height (4-8 cm), and hydraulic loading rate (2.0 and 4.0 m3/m2-day). After determining the optimal adsorption conditions, kinetics, isotherm, and breakthrough curve models were applied to analyze the experimental data. Peanut shells showed an irregular surface and consisted mainly of polysaccharides (around 70% lignin, cellulose, and hemicellulose), with a specific surface area of 1.7 m2/g and a pore volume of 0.005 cm3/g. The highest removal efficiencies for caffeine (85.6 ± 1.4%) and triclosan (89.3 ± 1.5%) were achieved using the smallest particles and 10.0 and 0.1 g/L doses over 180 and 45 min, respectively. Triclosan showed easier removal compared to caffeine due to its higher lipophilic character. The pseudo-second-order kinetics model provided the best fit with the experimental data, suggesting a chemisorption process between caffeine/triclosan and the adsorbent. Equilibrium data were well-described by the Sips model, with maximum adsorption capacities of 3.3 mg/g and 289.3 mg/g for caffeine and triclosan, respectively. In fixed-bed column adsorption tests, particle size significantly influenced efficiency and hydraulic behavior, with 120-150 µm particles exhibiting the highest adsorption capacity for caffeine (0.72 mg/g) and triclosan (143.44 mg/g), albeit with clogging issues. The experimental data also showed good agreement with the Bohart-Adams, Thomas, and Yoon-Nelson models. Therefore, the findings of this study highlight not only the effective capability of peanut shells to remove caffeine and triclosan but also their versatility as a promising option for water treatment and sanitation applications in different contexts.


Asunto(s)
Arachis , Cafeína , Triclosán , Cafeína/química , Cafeína/aislamiento & purificación , Triclosán/química , Triclosán/aislamiento & purificación , Arachis/química , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Tamaño de la Partícula , Purificación del Agua/métodos
18.
Chirurgia (Bucur) ; 119(1): 56-64, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38465716

RESUMEN

AIM: This study presents a comparative analysis of cryostripping to conventional saphenectomy. Materials and Methods: The study included 2191 patients admitted in the Phlebology Department, 1st Surgical Department, Emergency County Hospital Timisoara, between September 2013 and April 2023, between September 2013 and April 2023, who underwent saphenectomy by cryostripping (1327 patients) or conventionally (864 patients). We compared the duration and costs of the procedure, hospitalization period, post-operative results, method feasibility, as well as the technical advantages of cryostripping compared to conventional surgery. Results: A smaller proximal incision, compared to the classic operation, as well the fact that distal counter incision is not necessary, represents technical advantages of this procedure. Average duration of the intervention was 41 +- 12.8 minutes, consumables costs were about 52 +- 10 EUR/intervention, with an average hospitalization period was 1.05 +- 0.41 days. The post-operative results were favourable, early complications rate being reduced (ecchymoses Phi; 2 cm - 33.23%; hematoma - 2.11%; deep vein thrombosis - 0.15%; transient paresthesias 3.01%). Compared to classic saphenectomy, the costs of consumables/intervention are similar, intervention time, hospitalization period and complication rate being statistically significantly lower. An advantage of the method is the fact that the cryo-probes can be sterilized, being reusable; from the economic point of view, the technique perfectly fits in both public hospitals and private clinics. Conclusions: Cryostripping is a radical surgical procedure which bring a significant number of advantages compared to the classic saphenectomy, being an effective alternative in CVD treatment.


Asunto(s)
Vena Safena , Humanos , Resultado del Tratamiento , Estudios Retrospectivos , Vena Safena/cirugía
19.
Br J Haematol ; 200(3): 323-328, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36264026

RESUMEN

Drug resistance in chronic myeloid leukaemia (CML) may occur via mutations in the causative BCR::ABL1 fusion or BCR::ABL1-independent mechanisms. We analysed 48 patients with BCR::ABL1-independent resistance for the presence of secondary fusion genes by RNA sequencing. We identified 10 of the most frequently detected secondary fusions in 21 patients. Validation studies, cell line models, gene expression analysis and drug screening revealed differences with respect to proliferation rate, differentiation and drug sensitivity. Notably, expression of RUNX1::MECOM led to resistance to ABL1 tyrosine kinase inhibitors in vitro. These results suggest secondary fusions contribute to BCR::ABL1-independent resistance and may be amenable to combined therapies.


Asunto(s)
Proteínas de Fusión bcr-abl , Leucemia Mielógena Crónica BCR-ABL Positiva , Humanos , Proteínas de Fusión bcr-abl/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Mutación , Línea Celular , Resistencia a Antineoplásicos/genética
20.
Neurobiol Learn Mem ; 203: 107796, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37385521

RESUMEN

When a neutral stimulus is repeatedly paired with an appetitive reward, two different types of conditioned approach responses may develop: a sign-tracking response directed toward the neutral cue, or a goal-tracking response directed toward the location of impending reward delivery. Sign-tracking responses have been postulated to result from attribution of incentive value to conditioned cues, while goal-tracking reflects the assignment of only predictive value to the cue. We therefore hypothesized that sign-tracking rats would be more sensitive to manipulations of incentive value, while goal-tracking rats would be more responsive to changes in the predictive value of the cue. We tested sign- and goal-tracking before and after devaluation of a food reward using lithium chloride, and tested whether either response could be learned under negative contingency conditions that precluded any serendipitous reinforcement of the behavior that might support instrumental learning. We also tested the effects of blocking the predictive value of a cue using simultaneous presentation of a pre-conditioned cue. We found that sign-tracking was sensitive to outcome devaluation, while goal-tracking was not. We also confirmed that both responses are Pavlovian because they can be learned under negative contingency conditions. Goal-tracking was almost completely blocked by a pre-conditioned cue, while sign-tracking was much less sensitive to such interference. These results indicate that sign- and goal-tracking may follow different rules of reinforcement learning and suggest a need to revise current models of associative learning to account for these differences.


Asunto(s)
Objetivos , Motivación , Ratas , Animales , Ratas Sprague-Dawley , Refuerzo en Psicología , Recompensa , Señales (Psicología)
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