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Ever since microRNAs (miRNAs) were first recognized as an extensive gene family >20 years ago, a broad community of researchers was drawn to investigate the universe of small regulatory RNAs. Although core features of miRNA biogenesis and function were revealed early on, recent years continue to uncover fundamental information on the structural and molecular dynamics of core miRNA machinery, how miRNA substrates and targets are selected from the transcriptome, new avenues for multilevel regulation of miRNA biogenesis and mechanisms for miRNA turnover. Many of these latest insights were enabled by recent technological advances, including massively parallel assays, cryogenic electron microscopy, single-molecule imaging and CRISPR-Cas9 screening. Here, we summarize the current understanding of miRNA biogenesis, function and regulation, and outline challenges to address in the future.
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MicroARNs , MicroARNs/genética , TranscriptomaRESUMEN
The tissue-specific deployment of highly extended neural 3' UTR isoforms, generated by alternative polyadenylation (APA), is a broad and conserved feature of metazoan genomes. However, the factors and mechanisms that control neural APA isoforms are not well understood. Here, we show that three ELAV/Hu RNA binding proteins (Elav, Rbp9, and Fne) have similar capacities to induce a lengthened 3' UTR landscape in an ectopic setting. These factors promote accumulation of chromatin-associated, 3' UTR-extended, nascent transcripts, through inhibition of proximal polyadenylation site (PAS) usage. Notably, Elav represses an unannotated splice isoform of fne, switching the normally cytoplasmic Fne toward the nucleus in elav mutants. We use genomic profiling to reveal strong and broad loss of neural APA in elav/fne double mutant CNS, the first genetic background to largely abrogate this distinct APA signature. Overall, we demonstrate how regulatory interplay and functionally overlapping activities of neural ELAV/Hu RBPs drives the neural APA landscape.
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Regiones no Traducidas 3'/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Neuronas/metabolismo , Empalme Alternativo/genética , Secuencias de Aminoácidos , Animales , Línea Celular , Núcleo Celular/metabolismo , Proteínas ELAV/química , Larva/metabolismo , Mutación/genética , Poli A/metabolismo , Isoformas de Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
BACKGROUND: Data regarding clinical outcomes after intravascular imaging-guided percutaneous coronary intervention (PCI) for complex coronary-artery lesions, as compared with outcomes after angiography-guided PCI, are limited. METHODS: In this prospective, multicenter, open-label trial in South Korea, we randomly assigned patients with complex coronary-artery lesions in a 2:1 ratio to undergo either intravascular imaging-guided PCI or angiography-guided PCI. In the intravascular imaging group, the choice between intravascular ultrasonography and optical coherence tomography was at the operators' discretion. The primary end point was a composite of death from cardiac causes, target-vessel-related myocardial infarction, or clinically driven target-vessel revascularization. Safety was also assessed. RESULTS: A total of 1639 patients underwent randomization, with 1092 assigned to undergo intravascular imaging-guided PCI and 547 assigned to undergo angiography-guided PCI. At a median follow-up of 2.1 years (interquartile range, 1.4 to 3.0), a primary end-point event had occurred in 76 patients (cumulative incidence, 7.7%) in the intravascular imaging group and in 60 patients (cumulative incidence, 12.3%) in the angiography group (hazard ratio, 0.64; 95% confidence interval, 0.45 to 0.89; P = 0.008). Death from cardiac causes occurred in 16 patients (cumulative incidence, 1.7%) in the intravascular imaging group and in 17 patients (cumulative incidence, 3.8%) in the angiography group; target-vessel-related myocardial infarction occurred in 38 (cumulative incidence, 3.7%) and 30 (cumulative incidence, 5.6%), respectively; and clinically driven target-vessel revascularization in 32 (cumulative incidence, 3.4%) and 25 (cumulative incidence, 5.5%), respectively. There were no apparent between-group differences in the incidence of procedure-related safety events. CONCLUSIONS: Among patients with complex coronary-artery lesions, intravascular imaging-guided PCI led to a lower risk of a composite of death from cardiac causes, target-vessel-related myocardial infarction, or clinically driven target-vessel revascularization than angiography-guided PCI. (Supported by Abbott Vascular and Boston Scientific; RENOVATE-COMPLEX-PCI ClinicalTrials.gov number, NCT03381872).
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Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Infarto del Miocardio , Intervención Coronaria Percutánea , Humanos , Angiografía Coronaria/efectos adversos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/etiología , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Estudios Prospectivos , Resultado del Tratamiento , Ultrasonografía Intervencional/métodosRESUMEN
Haptic human-machine interfaces (HHMIs) combine tactile sensation and haptic feedback to allow humans to interact closely with machines and robots, providing immersive experiences and convenient lifestyles. Significant progress has been made in developing wearable sensors that accurately detect physical and electrophysiological stimuli with improved softness, functionality, reliability, and selectivity. In addition, soft actuating systems have been developed to provide high-quality haptic feedback by precisely controlling force, displacement, frequency, and spatial resolution. In this Review, we discuss the latest technological advances of soft sensors and actuators for the demonstration of wearable HHMIs. We particularly focus on highlighting material and structural approaches that enable desired sensing and feedback properties necessary for effective wearable HHMIs. Furthermore, promising practical applications of current HHMI technology in various areas such as the metaverse, robotics, and user-interactive devices are discussed in detail. Finally, this Review further concludes by discussing the outlook for next-generation HHMI technology.
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Dispositivos Electrónicos Vestibles , Humanos , Reproducibilidad de los ResultadosRESUMEN
Heat shock factor 1 (HSF-1) and forkhead box O (FOXO) are key transcription factors that protect cells from various stresses. In Caenorhabditis elegans, HSF-1 and FOXO together promote a long life span when insulin/IGF-1 signaling (IIS) is reduced. However, it remains poorly understood how HSF-1 and FOXO cooperate to confer IIS-mediated longevity. Here, we show that prefoldin 6 (PFD-6), a component of the molecular chaperone prefoldin-like complex, relays longevity response from HSF-1 to FOXO under reduced IIS. We found that PFD-6 was specifically required for reduced IIS-mediated longevity by acting in the intestine and hypodermis. We showed that HSF-1 increased the levels of PFD-6 proteins, which in turn directly bound FOXO and enhanced its transcriptional activity. Our work suggests that the prefoldin-like chaperone complex mediates longevity response from HSF-1 to FOXO to increase the life span in animals with reduced IIS.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Factores de Transcripción Forkhead/metabolismo , Longevidad/genética , Chaperonas Moleculares/metabolismo , Factores de Transcripción/metabolismo , Animales , Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Intestinos/fisiología , Chaperonas Moleculares/genética , Unión Proteica , Transducción de Señal/genética , Tejido Subcutáneo/fisiología , Activación Transcripcional/genéticaRESUMEN
Aging is associated with changes in a variety of biological processes at the transcriptomic level, including gene expression. Two types of aging occur during a lifetime: chronological and physiological aging. However, dissecting the difference between chronological and physiological ages at the transcriptomic level has been a challenge because of its complexity. We analyzed the transcriptomic features associated with physiological and chronological aging using Caenorhabditis elegans as a model. Many structural and functional transcript elements, such as noncoding RNAs and intron-derived transcripts, were up-regulated with chronological aging. In contrast, mRNAs with many biological functions, including RNA processing, were down-regulated with physiological aging. We also identified an age-dependent increase in the usage of distal 3' splice sites in mRNA transcripts as a biomarker of physiological aging. Our study provides crucial information for dissecting chronological and physiological aging at the transcriptomic level.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Envejecimiento/genética , Envejecimiento/metabolismo , Perfilación de la Expresión Génica , Proteínas de Caenorhabditis elegans/genética , TranscriptomaRESUMEN
Neuropathological features of Alzheimer's disease include amyloid plaques, neurofibrillary tangles and Lewy bodies, with the former preceding the latter two. However, it is not fully understood how these compound proteinopathies are interconnected. Here, we show that transplantation of amyloid-ß oligomer-activated microglia into the striatum of naïve mice was sufficient to generate all the features of Alzheimer's disease, including widespread tauopathy and synucleinopathy, gliosis, neuroinflammation, synapse loss, neuronal death, and cognitive and motor deficits. These pathological features were eliminated by microglia depletion and anti-inflammatory drug administration. Our results suggest the crucial roles of microglia-driven inflammation in development of mixed pathology. This study provides not only mechanistic insights into amyloid-ß oligomer-triggered proteinopathies but also a novel animal model recapitulating the salient features of Alzheimer's disease.
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Circular RNA (circRNA) is a closed, single-stranded transcript widely detected in eukaryotes. Recent studies indicate that the levels of circRNAs change with age in various tissues in multiple species, ranging from nematodes to mammals. Here we discuss the functional roles of circRNAs in animal aging and longevity. We review studies regarding the differential expression of circRNAs that contributes to cellular senescence and the pathogenesis of aging-associated diseases. We explore the features of aging-associated circRNAs by discussing their potential as biomarkers of aging, tissue specificity, physiological roles, action mechanisms, and evolutionarily conserved characteristics. Our review provides insights into current progress in circRNA research and their significant functions in the aging process.
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Envejecimiento/genética , ARN Circular/fisiología , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiología , Drosophila melanogaster/genética , Drosophila melanogaster/fisiología , Marcadores Genéticos , Humanos , Mamíferos/genética , Mamíferos/fisiologíaRESUMEN
Hepatic steatosis (HS) criteria for living donor liver transplantation (LDLT) donor eligibility should be based on large droplet fat as per Banff consensus recommendations. We aimed to establish MRI PDFF cut-offs for HS assessment in potential LDLT donors. This retrospective study included consecutive potential LDLT donors who underwent MRI and liver biopsy between 2013 and 2023 at two tertiary institutions, each as development (n=3062; 2015 men; median [interquartile range] age of 32 [25-38] years) and external validation (n=472; 287 men; 35 [26-44] years) datasets. PDFF was measured using dedicated MRI sequences. Histologic HS defined as large droplet fat fraction was used as the reference standard. Dual PDFF cut-offs aimed at 95% sensitivity or 95% specificity, for diagnosing histologic HS of ≥10%, ≥20%, ≥30%, and ≥40%, were determined in the development dataset using ten-fold cross validation. The cut-offs were then validated in the external validation dataset. Equation for estimating histologic HS from PDFF was also derived using linear regression. The PDFF cut-offs for histologic HS of ≥10%, ≥20%, ≥30%, and ≥40%, targeting 95% sensitivity, were 3.7%, 5.5%, 8.0%, and 10.0%, respectively. External validation demonstrated high sensitivities ≥ 97.9% with specificities ranging from 60.9% to 95.1%. The PDFF cut-offs targeting 95% specificity were 6.3%, 8.0%, 9.1%, and 10.1%, respectively. External validation rendered high specificities ranging from 88.5% to 95.3% with sensitivities ranging from 76.6% to 100%. For diagnosing histologic HS ≥30%, which is the most prevalently used threshold for LDLT donor eligibility assessment, the PDFF cut-offs achieved sensitivities and specificities of both over 90%. The equation of (Histologic HS=-2.95 + 1.93 * PDFF) was derived.
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INTRODUCTION: The long-term cognitive outcomes after transient global amnesia (TGA) have been contradictory in the literature. Our study aimed to longitudinally investigate the association between TGA and incident dementia using long-term data from a nationwide population-based cohort in South Korea. METHODS: The study population was recruited between 2002 and 2020 using the International Classification of Diseases (Tenth Revision; ICD-10) codes from the Korean National Health Insurance Service database. The cumulative incidence curve was plotted to compare the incidence of dementia between the TGA (ICD-10 code G45.4; n = 10,276) and non-TGA (n = 27,389) groups, determined using 1:3 propensity score matching. Using Cox proportional hazard regression models, we obtained crude and adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the incident dementia in patients with TGA compared to non-TGA controls. To examine independent variables determining dementia in the TGA group, logistic regression analysis was performed, and adjusted odds ratios (aORs) and 95% CIs were calculated. RESULTS: The TGA group had a significantly higher cumulative incidence of dementia than the non-TGA group (p < 0.001, log-rank test). TGA was significantly associated with incident dementia in the univariate and multivariate Cox models (HR 1.34, 95% CI 1.28-1.39 and aHR 1.40, 95% CI 1.34-1.46, respectively). The adjusted logistic regression for incident dementia in the TGA group showed that age (per 1 year, aOR 1.09, 95% CI 1.09-1.10), female sex (aOR 1.31, 95% CI 1.18-1.45), diabetes (aOR 1.21, 95% CI 1.08-1.35), stroke (aOR 1.30, 95% CI 1.16-1.46), depression (aOR 1.53, 95% CI 1.33-1.76), anxiety (aOR 1.24, 95% CI 1.01-1.39), and rural residence (aOR 1.24, 95% CI 1.10-1.41) were independently associated with incident dementia. CONCLUSION: Our results suggest a longitudinal association of TGA with incident dementia.
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Amnesia Global Transitoria , Demencia , Humanos , Masculino , Femenino , Demencia/epidemiología , República de Corea/epidemiología , Anciano , Estudios Longitudinales , Persona de Mediana Edad , Amnesia Global Transitoria/epidemiología , Estudios de Seguimiento , Incidencia , Factores de Riesgo , Anciano de 80 o más AñosRESUMEN
OBJECTIVES: To evaluate whether deep learning-based detection algorithms (DLD)-based triaging can reduce outpatient chest radiograph interpretation workload while maintaining noninferior sensitivity. METHODS: This retrospective study included patients who underwent initial chest radiography at the outpatient clinic between June 1 and June 30, 2017. Readers interpreted radiographs with/without a commercially available DLD that detects nine radiologic findings (atelectasis, calcification, cardiomegaly, consolidation, fibrosis, nodules, pneumothorax, pleural effusion, and pneumoperitoneum). The reading order was determined in a randomized, crossover manner. The radiographs were classified into negative and positive examinations. In a 50% worklist reduction scenario, radiographs were sorted in descending order of probability scores: the lower half was regarded as negative exams, while the remaining were read with DLD by radiologists. The primary analysis evaluated noninferiority in sensitivity between radiologists reading all radiographs and simulating a 50% worklist reduction, with the inferiority margin of 5%. The specificities were compared using McNemar's test. RESULTS: The study included 1964 patients (median age [interquartile range], 55 years [40-67 years]). The sensitivity was 82.6% (195 of 236; 95% CI: 77.5%, 87.3%) when readers interpreted all chest radiographs without DLD and 83.5% (197 of 236; 95% CI: 78.8%, 88.1%) in the 50% worklist reduction scenario. The difference in sensitivity was 0.8% (95% CI: - 3.8%, 5.5%), establishing noninferiority of 50% worklist reduction (p = 0.01). The specificity increased from 86.7% (1498 of 1728) to 90.4% (1562 of 1728) (p < 0.001) with DLD-based triage. CONCLUSION: Deep learning-based triaging may substantially reduce workload without lowering sensitivity while improving specificity. CLINICAL RELEVANCE STATEMENT: Substantial workload reduction without lowering sensitivity was feasible using deep learning-based triaging of outpatient chest radiograph; however, the legal responsibility for incorrect diagnoses based on AI-standalone interpretation remains an issue that should be defined before clinical implementation. KEY POINTS: ⢠A 50% workload reduction simulation using deep learning-based detection algorithm maintained noninferior sensitivity while improving specificity. ⢠The CT recommendation rate significantly decreased in the disease-negative patients, whereas it slightly increased in the disease-positive group without statistical significance. ⢠In the exploratory analysis, the noninferiority of sensitivity was maintained until 70% of the workload was reduced; the difference in sensitivity was 0%.
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Inteligencia Artificial , Aprendizaje Profundo , Humanos , Persona de Mediana Edad , Radiografía , Radiografía Torácica , Radiólogos , Estudios Retrospectivos , Sensibilidad y Especificidad , Triaje , Carga de Trabajo , Adulto , AncianoRESUMEN
OBJECTIVES: The carcinogenic risks of CT radiation in children and adolescents remain debated. We aimed to assess the carcinogenic risk of CTs performed in children and adolescents with minor head trauma. METHODS: In this nationwide population-based cohort study, we included 2,411,715 patients of age 0-19 with minor head trauma from 2009 to 2017. We excluded patients with elevated cancer risks or substantial past medical radiation exposure. Patients were categorized into CT-exposed or CT-unexposed group according to claim codes for head CT. The primary outcome was development of hematologic malignant neoplasms. Secondary outcomes included development of malignant solid neoplasms and benign neoplasms in the brain. We measured the incidence rate ratio (IRR) and incidence rate difference (IRD) using G-computation with Poisson regression adjusting for age, sex, hospital setting, and the type of head trauma. RESULTS: Hematologic malignant neoplasms developed in 100 of 216,826 patients during 1,303,680 person-years in the CT-exposed group and in 808 of 2,194,889 patients during 13,501,227 person-years in the CT-unexposed group. For hematologic malignant neoplasms, the IRR was 1.29 (95% CI, 1.03-1.60) and the IRD was 1.71 (95% CI, 0.04-3.37) per 100,000 person-years at risk. The majority of excess hematologic malignant neoplasms were leukemia (IRR, 1.40 [98.3% CI, 1.05-1.87]; IRD, 1.59 [98.3% CI, 0.02-3.16] per 100,000 person-years at risk). There were no between-group differences for secondary outcomes. CONCLUSIONS: Radiation exposure from head CTs in children and adolescents with minor head trauma was associated with an increased incidence of hematologic malignant neoplasms. CLINICAL RELEVANCE STATEMENT: Our study provides a quantitative grasp of the risk conferred by CT examinations in children and adolescents, thereby providing the basis for cost-benefit analyses and evidence-driven guidelines for patient triaging in head trauma. KEY POINTS: ⢠This nationwide population-based cohort study showed that radiation exposure from head CTs in children and adolescents was associated with a higher incidence of hematologic malignant neoplasms. ⢠The incidence rate of hematologic malignant neoplasms in the CT-exposed group was 29% higher than that in the CT-unexposed group (IRR, 1.29 [95% CI, 1.03-1.60]), and there were approximately 1.7 excess neoplasms per 100,000 person-years at risk in the CT-exposed group (IRD, 1.71 [0.04-3.37]). ⢠Our study provides a quantified grasp of the risk conferred by CT examinations in children and adolescents, while controlling for biases observed in previous studies via specifying CT indication and excluding patients with predisposing conditions for cancer development.
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Traumatismos Craneocerebrales , Neoplasias Hematológicas , Neoplasias Inducidas por Radiación , Tomografía Computarizada por Rayos X , Humanos , Adolescente , Niño , Femenino , Masculino , Preescolar , Traumatismos Craneocerebrales/diagnóstico por imagen , Traumatismos Craneocerebrales/epidemiología , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Inducidas por Radiación/etiología , Lactante , Neoplasias Hematológicas/epidemiología , Estudios de Cohortes , Recién Nacido , Incidencia , Adulto Joven , Taiwán/epidemiología , Factores de Riesgo , Exposición a la Radiación/efectos adversosRESUMEN
OBJECTIVE: Asthma is an airway inflammatory disease caused by activation of numerous immune cells including macrophages. Bakuchicin (BKC) is known to exhibit anti-inflammatory effects and type 2 T helper (Th2) regulation, but has not been investigated for airway inflammation. This study aimed to evaluate the effects of BKC on airway inflammation and demonstrate the mechanisms of macrophage polarization. METHODS: The anti-inflammatory effects were determined using lipopolysaccharide (LPS)-stimulated macrophages. The ovalbumin (OVA)-induced asthma mouse model was used to evaluate the effects of BKC on airway inflammation and Th2 responses. Moreover, the effect of BKC on macrophage polarization was confirmed in bone marrow-derived macrophages (BMDMs) differentiation. RESULTS: BKC suppressed nitric oxide production and expression of pro-inflammatory cytokines by inhibiting signaling pathway in LPS-stimulated macrophages. In an OVA-induced asthma model, BKC treatment alleviated histological changes and mast cell infiltration and reduced the levels of eosinophil peroxidase, ß-hexosaminidase, and immunoglobulin levels. In addition, BKC alleviated Th2 responses and M2 macrophage populations in bronchoalveolar fluid. In BMDMs, BKC suppressed IL-4-induced M2 macrophage polarization and the expression of M2 markers such as arginase-1 and Fizz-1 through inhibiting sirtuin 2 levels. CONCLUSION: BKC could be a drug candidate for the treatment of allergic asthma.
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Asma , Macrófagos , Ratones Endogámicos BALB C , Ovalbúmina , Animales , Asma/tratamiento farmacológico , Asma/inducido químicamente , Asma/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Femenino , Citocinas/metabolismo , Óxido Nítrico/metabolismo , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Células Th2/inmunología , Células Th2/efectos de los fármacos , Lipopolisacáridos , Pulmón/patología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Ratones Endogámicos C57BLRESUMEN
ELAV/Hu factors are conserved RNA binding proteins (RBPs) that play diverse roles in mRNA processing and regulation. The founding member, Drosophila Elav, was recognized as a vital neural factor 35 years ago. Nevertheless, little was known about its impacts on the transcriptome, and potential functional overlap with its paralogs. Building on our recent findings that neural-specific lengthened 3' UTR isoforms are co-determined by ELAV/Hu factors, we address their impacts on splicing. While only a few splicing targets of Drosophila are known, ectopic expression of each of the three family members (Elav, Fne and Rbp9) alters hundreds of cassette exon and alternative last exon (ALE) splicing choices. Reciprocally, double mutants of elav/fne, but not elav alone, exhibit opposite effects on both classes of regulated mRNA processing events in larval CNS. While manipulation of Drosophila ELAV/Hu RBPs induces both exon skipping and inclusion, characteristic ELAV/Hu motifs are enriched only within introns flanking exons that are suppressed by ELAV/Hu factors. Moreover, the roles of ELAV/Hu factors in global promotion of distal ALE splicing are mechanistically linked to terminal 3' UTR extensions in neurons, since both processes involve bypass of proximal polyadenylation signals linked to ELAV/Hu motifs downstream of cleavage sites. We corroborate the direct action of Elav in diverse modes of mRNA processing using RRM-dependent Elav-CLIP data from S2 cells. Finally, we provide evidence for conservation in mammalian neurons, which undergo broad programs of distal ALE and APA lengthening, linked to ELAV/Hu motifs downstream of regulated polyadenylation sites. Overall, ELAV/Hu RBPs orchestrate multiple broad programs of neuronal mRNA processing and isoform diversification in Drosophila and mammalian neurons.
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Empalme Alternativo/genética , Diferenciación Celular/genética , Proteínas de Drosophila/genética , Proteínas ELAV/genética , Proteína 1 Similar a ELAV/genética , Neuronas/metabolismo , Regiones no Traducidas 3'/genética , Animales , Sistema Nervioso Central/crecimiento & desarrollo , Sistema Nervioso Central/metabolismo , Humanos , Larva/genética , Larva/crecimiento & desarrollo , Proteínas del Tejido Nervioso/genética , Poliadenilación/genética , Procesamiento Postranscripcional del ARN/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Transcriptoma/genéticaRESUMEN
The Kuramoto model and its generalizations have been broadly employed to characterize and mechanistically understand various collective dynamical phenomena, especially the emergence of synchrony among coupled oscillators. Despite almost five decades of research, many questions remain open, in particular, for finite-size systems. Here, we generalize recent work [Thümler et al., Phys. Rev. Lett. 130, 187201 (2023)] on the finite-size Kuramoto model with its state variables analytically continued to the complex domain and also complexify its system parameters. Intriguingly, systems of two units with purely imaginary coupling do not actively synchronize even for arbitrarily large magnitudes of the coupling strengths, |K|â∞, but exhibit conservative dynamics with asynchronous rotations or librations for all |K|. For generic complex coupling, both traditional phase-locked states and asynchronous states generalize to complex locked states, fixed points off the real subspace that exist even for arbitrarily weak coupling. We analyze a new collective mode of rotations exhibiting finite, yet arbitrarily large rotation numbers. Numerical simulations for large networks indicate a novel form of discontinuous phase transition. We close by pointing to a range of exciting questions for future research.
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This research delves into advancing an ultra-wideband (UWB) localization system through the integration of filtering technologies (moving average (MVG), Kalman filter (KF), extended Kalman filter (EKF)) with a low-pass filter (LPF). We investigated new approaches to enhance the precision and reduce noise of the current filtering methods-MVG, KF, and EKF. Using a TurtleBot robotic platform with a camera, our research thoroughly examines the UWB system in various trajectory situations (square, circular, and free paths with 2 m, 2.2 m, and 5 m distances). Particularly in the square path trajectory with the lowest root mean square error (RMSE) values (40.22 mm on the X axis, and 78.71 mm on the Y axis), the extended Kalman filter with low-pass filter (EKF + LPF) shows notable accuracy. This filter stands out among the others. Furthermore, we find that integrated method using LPF outperforms MVG, KF, and EKF consistently, reducing the mean absolute error (MAE) to 3.39% for square paths, 4.21% for circular paths, and 6.16% for free paths. This study highlights the effectiveness of EKF + LPF for accurate indoor localization for UWB systems.
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Environmental fluctuations influence organismal aging by affecting various regulatory systems. One such system involves sensory neurons, which affect life span in many species. However, how sensory neurons coordinate organismal aging in response to changes in environmental signals remains elusive. Here, we found that a subset of sensory neurons shortens Caenorhabditis elegans' life span by differentially regulating the expression of a specific insulin-like peptide (ILP), INS-6. Notably, treatment with food-derived cues or optogenetic activation of sensory neurons significantly increases ins-6 expression and decreases life span. INS-6 in turn relays the longevity signals to nonneuronal tissues by decreasing the activity of the transcription factor DAF-16/FOXO. Together, our study delineates a mechanism through which environmental sensory cues regulate aging rates by modulating the activities of specific sensory neurons and ILPs.
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Proteínas de Caenorhabditis elegans/genética , Alimentos , Factores de Transcripción Forkhead/genética , Regulación de la Expresión Génica , Insulina/genética , Longevidad/genética , Hormonas Peptídicas/genética , Proteínas de Caenorhabditis elegans/metabolismo , Señales (Psicología) , Ambiente , Factores de Transcripción Forkhead/metabolismo , Insulina/metabolismo , Optogenética , Hormonas Peptídicas/metabolismo , Células Receptoras Sensoriales/fisiología , Transducción de SeñalRESUMEN
Metastatic cancer cells can develop anoikis resistance in the absence of substrate attachment and survive to fight tumors. Anoikis is mediated by endogenous mitochondria-dependent and exogenous death receptor pathways, and studies have shown that caspase-8-dependent external pathways appear to be more important than the activity of the intrinsic pathways. This paper reviews the regulation of anoikis by external pathways mediated by death receptors. Different death receptors bind to different ligands to activate downstream caspases. The possible mechanisms of Fas-associated death domain (FADD) recruitment by Fas and TNF receptor 1 associated-death domain (TRADD) recruitment by tumor necrosis factor receptor 1 (TNFR1), and DR4- and DR5-associated FADD to induce downstream caspase activation and regulate anoikis were reviewed. This review highlights the possible mechanism of the death receptor pathway mediation of anoikis and provides new insights and research directions for studying tumor metastasis mechanisms. Video Abstract.
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Anoicis , Caspasas , Proteolisis , Mitocondrias , Procesamiento Proteico-PostraduccionalRESUMEN
BACKGROUND. Pathologic extranodal extension (ENE) in metastatic lymph nodes (LNs) has been associated with unfavorable prognosis in patients with non-small cell lung cancer (NSCLC). OBJECTIVE. The purpose of this article was to evaluate the prognostic utility of radiologic ENE and its diagnostic performance in predicting pathologic ENE in patients with NSCLC. METHODS. This retrospective study included 382 patients (mean age, 67 ± 10 [SD] years; 297 men, 85 women) diagnosed with NSCLC and clinical N1 or N2 disease between January 2010 and December 2016. Two thoracic radiologists reviewed staging chest CT examinations to record subjective overall impression for radiologic ENE (no ENE, possible/probable ENE, or unambiguous ENE), reviewing 30 examinations in consensus and the remaining examinations independently. Kaplan-Meier survival analysis and multivariable Cox proportional hazards model were used to evaluate the utility of radiologic ENE in predicting overall survival (OS). Prognostic utility of radiologic ENE was also assessed in patients with clinical N2a disease. In patients who underwent surgery, sensitivity and specificity were determined of radiologic unambiguous ENE in predicting pathologic ENE. RESULTS. The 5-year OS rates for no ENE, possible/probable ENE, and unambiguous ENE were 44.4%, 39.1%, and 20.9% for reader 1 and 45.7%, 36.6%, and 25.6% for reader 2, respectively. Unambiguous ENE was an independent prognostic factor for worse OS (reader 1: adjusted HR, 1.72, p = .008; reader 2: adjusted HR, 1.56, p = .03), whereas possible/probable ENE was not (reader 1: adjusted HR, 1.18, p = .33; reader 2: adjusted HR, 1.21, p = .25). In patients with clinical N2a disease, 5-year OS rate in patients with versus without unambiguous ENE for reader 1 was 22.2% versus 40.6% (p = .59) and for reader 2 was 27.6% versus 41.0% (p = .49). In 203 patients who underwent surgery (66 with pathologic ENE), sensitivity and specificity of radiologic unambiguous ENE for predicting pathologic ENE were 11% and 93% for reader 1 and 23% and 87% for reader 2. CONCLUSION. Radiologic unambiguous ENE was an independent predictor of worse OS in patients with NSCLC. The finding had low sensitivity but high specificity for pathologic ENE. CLINICAL IMPACT. Radiologic ENE may have a role in NSCLC staging workup and treatment selection.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Pronóstico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Extensión Extranodal/patología , Estudios Retrospectivos , Estadificación de Neoplasias , Neoplasias Pulmonares/patología , Ganglios Linfáticos/patologíaRESUMEN
BACKGROUND. Staging chest CT has been shown to have negligible diagnostic yield for detecting lung metastases in patients with early-stage colon cancer. Nonetheless, staging chest CT may have potential survival benefits, including opportunistic screening of comorbidity and provision of a baseline examination for future comparisons. Evidence is lacking regarding the impact of staging chest CT on survival in patients with early-stage colon cancer. OBJECTIVE. The purpose of this study was to determine whether the performance of staging chest CT affects survival in patients with early-stage colon cancer. METHODS. This retrospective study included patients with early-stage colon cancer (defined as clinical stage 0 or I on staging abdominal CT) at a single tertiary hospital between January 2009 and December 2015. Patients were divided into two groups according to the presence of a staging chest CT examination. To ensure comparability between the two groups, inverse probability weighting was applied to adjust for the confounders derived from a causal diagram. The between-group differences in adjusted restricted mean survival time at 5 years were measured for overall survival, relapse-free survival, and thoracic metastasis-free survival. Sensitivity analyses were performed. RESULTS. A total of 991 patients (618 men and 373 women; median age, 64 years [IQR, 55-71 years]) were included: 606 patients (61.2%) had staging chest CT. For overall survival, the difference between groups in restricted mean survival time at 5 years was not significant (0.4 months [95% CI, -0.8 to 2.1 months]). The differences between groups in restricted mean survival at 5 years were also not significant for relapse-free survival (0.4 months [95% CI, -1.1 to 2.3 months]) and for thoracic metastasis-free survival (0.6 months [95% CI, -0.8 to 2.4 months]). Similar results were observed in sensitivity analyses that tested 3- and 10-year RMST differences, excluded patients who underwent FDG PET/CT during staging workup, and added treatment decision (surgery vs no surgery) to the causal diagram. CONCLUSION. The use of staging chest CT did not affect survival in patients with early-stage colon cancer. CLINICAL IMPACT. Staging chest CT may be omitted from the staging workup for patients with colon cancer of clinical stage 0 or I.