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1.
Cell ; 177(4): 942-956.e14, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30955889

RESUMEN

Plants are sessile and have to cope with environmentally induced damage through modification of growth and defense pathways. How tissue regeneration is triggered in such responses and whether this involves stem cell activation is an open question. The stress hormone jasmonate (JA) plays well-established roles in wounding and defense responses. JA also affects growth, which is hitherto interpreted as a trade-off between growth and defense. Here, we describe a molecular network triggered by wound-induced JA that promotes stem cell activation and regeneration. JA regulates organizer cell activity in the root stem cell niche through the RBR-SCR network and stress response protein ERF115. Moreover, JA-induced ERF109 transcription stimulates CYCD6;1 expression, functions upstream of ERF115, and promotes regeneration. Soil penetration and response to nematode herbivory induce and require this JA-mediated regeneration response. Therefore, the JA tissue damage response pathway induces stem cell activation and regeneration and activates growth after environmental stress.


Asunto(s)
Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Raíces de Plantas/metabolismo , Células Madre/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ciclinas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Herbivoria , Ácidos Indolacéticos/metabolismo , Regeneración/fisiología , Transducción de Señal/fisiología , Estrés Fisiológico , Factores de Transcripción/metabolismo
2.
Trends Biochem Sci ; 46(8): 673-686, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33558127

RESUMEN

The ATG8 family proteins are critical players in autophagy, a cytoprotective process that mediates degradation of cytosolic cargo. During autophagy, ATG8s conjugate to autophagosome membranes to facilitate cargo recruitment, autophagosome biogenesis, transport, and fusion with lysosomes, for cargo degradation. In addition to these canonical functions, recent reports demonstrate that ATG8s are also delivered to single-membrane organelles, which leads to highly divergent degradative or secretory fates, vesicle maturation, and cargo specification. The association of ATG8s with different vesicles involves complex regulatory mechanisms still to be fully elucidated. Whether individual ATG8 family members play unique canonical or non-canonical roles, also remains unclear. This review summarizes the many open molecular questions regarding ATG8s that are only beginning to be unraveled.


Asunto(s)
Autofagia , Proteínas Asociadas a Microtúbulos , Autofagosomas , Familia de las Proteínas 8 Relacionadas con la Autofagia , Proteínas Relacionadas con la Autofagia , Lisosomas
3.
Plant J ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864847

RESUMEN

Plants continuously endure unpredictable environmental fluctuations that upset their physiology, with stressful conditions negatively impacting yield and survival. As a contemporary threat of rapid progression, global warming has become one of the most menacing ecological challenges. Thus, understanding how plants integrate and respond to elevated temperatures is crucial for ensuring future crop productivity and furthering our knowledge of historical environmental acclimation and adaptation. While the canonical heat-shock response and thermomorphogenesis have been extensively studied, evidence increasingly highlights the critical role of regulatory epigenetic mechanisms. Among these, the involvement under heat of heterochromatic suppression mediated by transcriptional gene silencing (TGS) remains the least understood. TGS refers to a multilayered metabolic machinery largely responsible for the epigenetic silencing of invasive parasitic nucleic acids and the maintenance of parental imprints. Its molecular effectors include DNA methylation, histone variants and their post-translational modifications, and chromatin packing and remodeling. This work focuses on both established and emerging insights into the contribution of TGS to the physiology of plants under stressful high temperatures. We summarized potential roles of constitutive and facultative heterochromatin as well as the most impactful regulatory genes, highlighting events where the loss of epigenetic suppression has not yet been associated with corresponding changes in epigenetic marks.

4.
Plant J ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963754

RESUMEN

DNA glycosylases initiate the base excision repair (BER) pathway by catalyzing the removal of damaged or mismatched bases from DNA. The Arabidopsis DNA glycosylase methyl-CpG-binding domain protein 4 like (MBD4L) is a nuclear enzyme triggering BER in response to the genotoxic agents 5-fluorouracil and 5-bromouracil. To date, the involvement of MBD4L in plant physiological processes has not been analyzed. To address this, we studied the enzyme functions in seeds. We found that imbibition induced the MBD4L gene expression by generating two alternative transcripts, MBD4L.3 and MBD4L.4. Gene activation was stronger in aged than in non-aged seeds. Seeds from mbd4l-1 mutants displayed germination failures when maintained under control or ageing conditions, while 35S:MBD4L.3/mbd4l-1 and 35S:MBD4L.4/mbd4l-1 seeds reversed these phenotypes. Seed nuclear DNA repair, assessed by comet assays, was exacerbated in an MBD4L-dependent manner at 24 h post-imbibition. Under this condition, the BER genes ARP, APE1L, and LIG1 showed higher expression in 35S:MBD4L.3/mbd4l-1 and 35S:MBD4L.4/mbd4l-1 than in mbd4l-1 seeds, suggesting that these components could coordinate with MBD4L to repair damaged DNA bases in seeds. Interestingly, the ATM, ATR, BRCA1, RAD51, and WEE1 genes associated with the DNA damage response (DDR) pathway were activated in mbd4l-1, but not in 35S:MBD4L.3/mbd4l-1 or 35S:MBD4L.4/mbd4l-1 seeds. These results indicate that MBD4L is a key enzyme of a BER cascade that operates during seed imbibition, whose deficiency would cause genomic damage detected by DDR, generating a delay or reduction in germination.

5.
J Cell Sci ; 136(16)2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37589340

RESUMEN

Autophagy is a recycling mechanism involved in cellular homeostasis with key implications for health and disease. The conjugation of the ATG8 family proteins, which includes LC3B (also known as MAP1LC3B), to autophagosome membranes, constitutes a hallmark of the canonical autophagy process. After ATG8 proteins are conjugated to the autophagosome membranes via lipidation, they orchestrate a plethora of protein-protein interactions that support key steps of the autophagy process. These include binding to cargo receptors to allow cargo recruitment, association with proteins implicated in autophagosome transport and autophagosome-lysosome fusion. How these diverse and critical protein-protein interactions are regulated is still not well understood. Recent reports have highlighted crucial roles for post-translational modifications of ATG8 proteins in the regulation of ATG8 functions and the autophagy process. This Review summarizes the main post-translational regulatory events discovered to date to influence the autophagy process, mostly described in mammalian cells, including ubiquitylation, acetylation, lipidation and phosphorylation, as well as their known contributions to the autophagy process, physiology and disease.


Asunto(s)
Autofagia , Procesamiento Proteico-Postraduccional , Animales , Familia de las Proteínas 8 Relacionadas con la Autofagia/genética , Fosforilación , Autofagosomas , Mamíferos
6.
Plant Physiol ; 195(1): 799-811, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38330218

RESUMEN

The transcription factor WUSCHEL-RELATED HOMEOBOX 11 (WOX11) in Arabidopsis (Arabidopsis thaliana) initiates the formation of adventitious lateral roots upon mechanical injury in primary roots. Root-invading nematodes also induce de novo root organogenesis leading to excessive root branching, but it is not known if this symptom of disease involves mediation by WOX11 and if it benefits the plant. Here, we show with targeted transcriptional repression and reporter gene analyses in Arabidopsis that the beet cyst nematode Heterodera schachtii activates WOX11-mediated adventitious lateral rooting from primary roots close to infection sites. The activation of WOX11 in nematode-infected roots occurs downstream of jasmonic acid-dependent damage signaling via ETHYLENE RESPONSE FACTOR109, linking adventitious lateral root formation to nematode damage to host tissues. By measuring different root system components, we found that WOX11-mediated formation of adventitious lateral roots compensates for nematode-induced inhibition of primary root growth. Our observations further demonstrate that WOX11-mediated rooting reduces the impact of nematode infections on aboveground plant development and growth. Altogether, we conclude that the transcriptional regulation by WOX11 modulates root system plasticity under biotic stress, which is one of the key mechanisms underlying the tolerance of Arabidopsis to cyst nematode infections.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas , Factores de Transcripción , Tylenchoidea , Animales , Raíces de Plantas/parasitología , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Arabidopsis/parasitología , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Tylenchoidea/fisiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/genética , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Plantas Modificadas Genéticamente
7.
Int Immunol ; 36(3): 111-128, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38066638

RESUMEN

Nurr1 is a member of the orphan nuclear receptor family NR4A (nuclear receptor subfamily 4 group A) that modulates inflammation in several cell lineages, both positively and negatively. Macrophages are key regulators of inflammatory responses, yet information about the role of Nurr1 in human macrophages is scarce. Here we examined Nurr1 expression and activity in steady state and activated human macrophages. Pro- and anti-inflammatory macrophages were generated in vitro by culture of blood monocytes with granulocyte/macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF), respectively. Nurr1 expression was predominant in macrophages with the pro-inflammatory phenotype. Nurr1 activation with the agonists 1,1-bis(3'-indolyl)-1-(p-chlorophenyl) methane (C-DIM12) or isoxazolo-pyridinone 7e (IP7e) did not globally modify the polarization status of pro-inflammatory macrophages, but they decreased their production of TNF, IL-1ß, IL-6, IL-8, IL-12 p40, CCL2, IFN-ß, and reactive oxygen species, with variable potencies. Conversely, Nurr1 deficient macrophages increased the expression of transcripts encoding inflammatory mediators, particularly that of IL6, IFNB1, and CCL2. Mechanistically, endogenous Nurr1 interacted with NF-κB p65 in basal conditions and upon lipopolysaccharide (LPS)-mediated activation. C-DIM12 stabilized those complexes in cells exposed to LPS and concurrently decreased NF-κB transcriptional activity and p65 nuclear translocation. Expression of high levels of Nurr1 was associated with a subset of dermal macrophages that display enhanced levels of TNF and lower expression of the anti-inflammatory marker CD163L1 in skin lesions from patients with bullous pemphigoid (BP), a chronic inflammatory autoimmune blistering disorder. These results suggest that Nurr1 expression is linked with the pro-inflammatory phenotype of human macrophages, both in vivo and in vitro, where it may constitute a brake to attenuate the synthesis of inflammatory mediators.


Asunto(s)
Factor Estimulante de Colonias de Macrófagos , FN-kappa B , Humanos , FN-kappa B/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Antiinflamatorios/metabolismo
8.
Plant J ; 115(6): 1633-1646, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37278489

RESUMEN

DNA glycosylases remove mispaired or modified bases from DNA initiating the base excision repair (BER) pathway. The DNA glycosylase MBD4 (methyl-CpG-binding domain protein 4) has been functionally characterized in mammals, but not yet in plants, where it is called MBD4-like (MBD4L). Mammalian MBD4 and Arabidopsis recombinant MBD4L excise U and T mispaired with G, as well as 5-fluorouracil (5-FU) and 5-bromouracil (5-BrU) in vitro. Here, we investigate the ability of Arabidopsis MBD4L to remove some of these substrates from the nuclear genome in vivo in coordination with uracil DNA glycosylase (AtUNG). We found that mbd4l mutants are hypersensitive to 5-FU and 5-BrU, as they displayed smaller size, less root growth, and higher cell death than control plants in both media. Using comet assays, we determined BER-associated DNA fragmentation in isolated nuclei and observed reduced DNA breaks in mbd4l plants under both conditions, but particularly with 5-BrU. The use of ung and ung x mbd4l mutants in these assays indicated that both MBD4L and AtUNG trigger nuclear DNA fragmentation in response to 5-FU. Consistently, we here report the nuclear localization of AtUNG based on the expression of AtUNG-GFP/RFP constructs in transgenic plants. Interestingly, MBD4L and AtUNG are transcriptionally coordinated but display not completely overlapping functions. MBD4L-deficient plants showed reduced expression of BER genes and enhanced expression of DNA damage response (DDR) gene markers. Overall, our findings indicate that Arabidopsis MBD4L is critical for maintaining nuclear genome integrity and preventing cell death under genotoxic stress conditions.


Asunto(s)
Arabidopsis , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , ADN/metabolismo , Daño del ADN , Reparación del ADN/genética , Fluorouracilo/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Uracil-ADN Glicosidasa/genética , Uracil-ADN Glicosidasa/metabolismo
9.
J Neurooncol ; 167(1): 99-109, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38351343

RESUMEN

INTRODUCTION: Recent studies have identified that glioblastoma IDH-wildtype consists of different molecular subgroups with distinct prognoses. In order to accurately describe and classify gliomas, the Visually AcceSAble Rembrandt Images (VASARI) system was developed. The goal of this study was to evaluate the VASARI characteristics in molecular subgroups of IDH-wildtype glioblastoma. METHODS: A retrospective analysis of glioblastoma IDH- wildtype with comprehensive next-generation sequencing and pre-operative and post-operative MRI was performed. VASARI characteristics and 205 genes were evaluated. Multiple comparison adjustment by the Bejamin-Hochberg false discovery rate (BH-FDR) was performed. A 1:3 propensity score match (PSM) with a Caliper of 0.2 was done. RESULTS: 178 patients with GBM IDH-WT met the inclusion criteria. 4q12 amplified patients (n = 20) were associated with cyst presence (30% vs. 12%, p = 0.042), decreased hemorrhage (35% vs. 62%, p = 0.028), and non-restricting/mixed (35%/60%) rather than restricting diffusion pattern (5%), meanwhile, 4q12 non-amplified patients had mostly restricting (47.4%) rather than a non-restricting/mixed diffusion pattern (28.4%/23.4%). This remained statistically significant after BH-FDR adjustment (p = 0.002). PSM by 4q12 amplification showed that diffusion characteristics continued to be significantly different. Among RB1-mutant patients, 96% had well-defined enhancing margins vs. 70.6% of RB1-WT (p = 0.018), however, this was not significant after BH-FDR or PSM. CONCLUSIONS: Patients with glioblastoma IDH-wildtype harboring 4q12 amplification rarely have restricting DWI patterns compared to their wildtype counterparts, in which this DWI pattern is present in ~ 50% of patients. This suggests that some phenotypic imaging characteristics can be identified among molecular subtypes of IDH-wildtype glioblastoma.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/diagnóstico por imagen , Glioblastoma/genética , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Estudios Retrospectivos , Glioma/genética , Pronóstico , Isocitrato Deshidrogenasa/genética , Mutación , Ubiquitina-Proteína Ligasas/genética , Proteínas de Unión a Retinoblastoma/genética
10.
J Neuropsychiatry Clin Neurosci ; 36(1): 36-44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37667629

RESUMEN

OBJECTIVE: A significant number of patients develop anxiety after stroke. The objective of this study was to identify risk factors for anxiety after hemorrhagic stroke that may facilitate diagnosis and treatment. METHODS: Patients admitted between January 2015 and February 2021 with nontraumatic hemorrhagic stroke (intracerebral [ICH] or subarachnoid [SAH] hemorrhage) were assessed telephonically 3 and 12 months after stroke with the Quality of Life in Neurological Disorders Anxiety Short Form to evaluate the relationships between poststroke anxiety (T score >50) and preclinical social and neuropsychiatric history, systemic and neurological illness severity, and in-hospital complications. RESULTS: Of 71 patients who completed the 3-month assessment, 28 (39%) had anxiety. There was a difference in Glasgow Coma Scale (GCS) scores on admission between patients with anxiety (median=14, interquartile range [IQR]=12-15) and those without anxiety (median=15, IQR=14-15) (p=0.034), and the incidence of anxiety was higher among patients with ICH (50%) than among those with SAH (20%) (p=0.021). Among patients with ICH, anxiety was associated with larger median ICH volume (25 cc [IQR=8-46] versus 8 cc [IQR=3-13], p=0.021) and higher median ICH score (2 [IQR=1-3] versus 1 [IQR=0-1], p=0.037). On multivariable analysis with GCS score, hemorrhage type, and neuropsychiatric history, only hemorrhage type remained significant (odds ratio=3.77, 95% CI=1.19-12.05, p=0.024). Of the 39 patients who completed the 12-month assessment, 12 (31%) had anxiety, and there was a difference in mean National Institutes of Health Stroke Scale scores between patients with (5 [IQR=3-12]) and without (2 [IQR=0-4]) anxiety (p=0.045). There was fair agreement (κ=0.38) between the presence of anxiety at 3 and 12 months. CONCLUSIONS: Hemorrhage characteristics and factors assessed with neurological examination on admission are associated with the development of poststroke anxiety.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular , Hemorragia Subaracnoidea , Humanos , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/epidemiología , Accidente Cerebrovascular Hemorrágico/complicaciones , Calidad de Vida , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/epidemiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología , Ansiedad/epidemiología , Ansiedad/etiología , Factores de Riesgo
11.
J Neuropsychiatry Clin Neurosci ; : appineuropsych20230114, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38650464

RESUMEN

OBJECTIVE: Emotional and behavioral dyscontrol (EBD), a neuropsychiatric complication of stroke, leads to patient and caregiver distress and challenges to rehabilitation. Studies of neuropsychiatric sequelae in stroke are heavily weighted toward ischemic stroke. This study was designed to compare risk of EBD following intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) and to identify risk factors for EBD following hemorrhagic stroke. METHODS: The authors conducted a prospective cohort study of patients hospitalized for nontraumatic hemorrhagic stroke between 2015 and 2021. Patients or legally authorized representatives completed the Quality of Life in Neurological Disorders (Neuro-QOL) EBD short-form inventory 3 months after hospitalization. Univariable and multivariable analyses identified risk factors for EBD after hemorrhagic stroke. RESULTS: The incidence of EBD was 21% (N=15 of 72 patients) at 3 months after hemorrhagic stroke. Patients with ICH were more likely to develop EBD; 93% of patients with EBD (N=14 of 15) had ICH compared with 56% of patients without EBD (N=32 of 57). The median Glasgow Coma Scale (GCS) score at hospital admission was lower among patients who developed EBD (13 vs. 15 among those without EBD). Similarly, admission scores on the National Institutes of Health Stroke Scale (NIHSS) and the Acute Physiology and Chronic Health Evaluation II (APACHE II) were higher among patients with EBD (median NIHSS score: 7 vs. 2; median APACHE II score: 17 vs. 11). Multivariable analyses identified hemorrhage type (ICH) and poor admission GCS score as predictors of EBD 3 months after hemorrhagic stroke. CONCLUSIONS: Patients with ICH and a low GCS score at admission are at increased risk of developing EBD 3 months after hemorrhagic stroke and may benefit from early intervention.

12.
J Chem Phys ; 160(20)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804486

RESUMEN

The melting temperature is important for materials design because of its relationship with thermal stability, synthesis, and processing conditions. Current empirical and computational melting point estimation techniques are limited in scope, computational feasibility, or interpretability. We report the development of a machine learning methodology for predicting melting temperatures of binary ionic solid materials. We evaluated different machine-learning models trained on a dataset of the melting points of 476 non-metallic crystalline binary compounds using materials embeddings constructed from elemental properties and density-functional theory calculations as model inputs. A direct supervised-learning approach yields a mean absolute error of around 180 K but suffers from low interpretability. We find that the fidelity of predictions can further be improved by introducing an additional unsupervised-learning step that first classifies the materials before the melting-point regression. Not only does this two-step model exhibit improved accuracy, but the approach also provides a level of interpretability with insights into feature importance and different types of melting that depend on the specific atomic bonding inside a material. Motivated by this finding, we used a symbolic learning approach to find interpretable physical models for the melting temperature, which recovered the best-performing features from both prior models and provided additional interpretability.

13.
BMC Pediatr ; 24(1): 141, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413925

RESUMEN

BACKGROUND: The assessment of cardiorespiratory fitness is important because it allows the identification of subgroups with poor health status and the targeting of effective intervention strategies to improve health. OBJECTIVE: To compare the cardiorespiratory capacity of children and adolescents living in a moderate altitude region of Peru with international studies and to develop reference values for the 6-min walk test (6MWT) according to age and sex. METHODOLOGY: A descriptive cross-sectional study of schoolchildren from a region of moderate altitude in Peru was carried out. A total of 704 schoolchildren (400 males and 304 females) with an age range of 6 to 17 years were studied. Weight, standing height, waist circumference (WC), body mass index (BMI) and tri-ponderal mass index (TMI) were evaluated. The 6MWT was assessed in a straight line over a distance of 30 m. Percentiles were created through the LMS method [L (skewness: lambda), M (median: mu) and S (coefficient of variation: Mu)]. RESULTS: There were discrepancies in cardiorespiratory fitness performance with international studies by age and sex. The schoolchildren in the study reached stability and the highest number of meters in the last two age ranges (14 to 15 years: 698.1 m and 16 to 17 years 686.3 m in males). While females (14 to 15 years: 698.1 m and 16 to 17 years: 686.3 m). The proposed percentile values show ascending values as age advances. The cut-off points adopted are: low cardiorespiratory fitness < p25, moderate p25 to p75 and high cardiorespiratory fitness p > 75. CONCLUSION: We verified that the cardiorespiratory fitness evaluated by means of the 6MWT is ascending with the course of age. Even the performance with other countries is heterogeneous at early and middle ages, stabilizing during adolescence. The proposed reference values can be used to evaluate and monitor cardiorespiratory fitness during physical education classes.


Asunto(s)
Altitud , Caminata , Masculino , Femenino , Niño , Humanos , Adolescente , Prueba de Paso , Valores de Referencia , Estudios Transversales , Perú , Índice de Masa Corporal
14.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34465618

RESUMEN

The efficiency of the synthesis of renewable fuels and feedstocks from electrical sources is limited, at present, by the sluggish water oxidation reaction. Single-atom catalysts (SACs) with a controllable coordination environment and exceptional atom utilization efficiency open new paradigms toward designing high-performance water oxidation catalysts. Here, using operando X-ray absorption spectroscopy measurements with calculations of spectra and electrochemical activity, we demonstrate that the origin of water oxidation activity of IrNiFe SACs is the presence of highly oxidized Ir single atom (Ir5.3+) in the NiFe oxyhydroxide under operating conditions. We show that the optimal water oxidation catalyst could be achieved by systematically increasing the oxidation state and modulating the coordination environment of the Ir active sites anchored atop the NiFe oxyhydroxide layers. Based on the proposed mechanism, we have successfully anchored Ir single-atom sites on NiFe oxyhydroxides (Ir0.1/Ni9Fe SAC) via a unique in situ cryogenic-photochemical reduction method that delivers an overpotential of 183 mV at 10 mA ⋅ cm-2 and retains its performance following 100 h of operation in 1 M KOH electrolyte, outperforming the reported catalysts and the commercial IrO2 catalysts. These findings open the avenue toward an atomic-level understanding of the oxygen evolution of catalytic centers under in operando conditions.

15.
Vascular ; : 17085381241262927, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38876778

RESUMEN

OBJECTIVES: Carotid interventions are indicated for both patients with symptomatic and a subset of patients with severe asymptomatic carotid artery stenosis (CAS). Symptomatic CAS accounts for up to 12%-25% of overall carotid interventions, but predictors of symptomatic presentation remain poorly defined. The aim of this study was to identify factors associated with symptomatic CAS in our patient population. METHODS: Between January 2015 and February 2022, an institutional retrospective cohort study of prospectively collected data on patients undergoing interventions for CAS was performed. Procedures included carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), and transfemoral carotid artery stenting (TF-CAS). Demographic data, comorbidities, procedural details, and anatomic features from various imaging modalities were collected. Comparisons were made between symptomatic (symptoms within the prior 6 months) and asymptomatic patients. RESULTS: During the study period, 279 patients who underwent intervention for symptomatic CAS were paired with a randomly selected cohort of 300 patients who underwent intervention for asymptomatic CAS from a total patient cohort of 1143 patients undergoing interventions for asymptomatic CAS. Demographic data did not differ between groups. Patients with symptomatic CAS more frequently had prior TIA/stroke (>6 months remote to the current event), but less frequently had coronary artery disease or chronic kidney disease and were less likely to receive adequate medical management including antihypertensive agents, lipid-lowering agents, and anti-platelet therapy. On multivariate analysis, remote prior TIA/stroke and lack of anti-platelet therapy remained significant. Among symptomatic patients presenting with stroke, lack of anti-platelet therapy was associated with an overall larger area of parenchymal involvement. No difference was observed with single versus dual anti-platelet therapy. Furthermore, symptomatic patients were more likely to have ulcerated plaques (30.9% vs 18%, p < .001), and symptomatic patients with ulcerated plaques more frequently had less than 50% compared to moderate/severe CAS. Nine patients who presented with symptoms had mild CAS and underwent intervention. CONCLUSIONS: Symptomatic CAS was associated with a history of remote prior symptoms and lack of anti-platelet therapy at time of presentation. Furthermore, symptomatic patients not on anti-platelet agents were more likely to have a greater area of parenchymal involvement when presenting with stroke and symptomatic patients with ulcerated plaques were more likely to have mild CAS, suggesting the role of plaque instability in symptomatic presentation. These findings underscore the importance of appropriate medical management and adherence in all patients with CAS and perhaps a role for more frequent surveillance in those with potentially unstable plaque morphology.

16.
Sensors (Basel) ; 24(7)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38610447

RESUMEN

In Portugal, more than 98% of domestic cooking oil is disposed of improperly every day. This avoids recycling/reconverting into another energy. Is also may become a potential harmful contaminant of soil and water. Driven by the utility of recycled cooking oil, and leveraging the exponential growth of ubiquitous computing approaches, we propose an IoT smart solution for domestic used cooking oil (UCO) collection bins. We call this approach SWAN, which stands for Smart Waste Accumulation Network. It is deployed and evaluated in Portugal. It consists of a countrywide network of collection bin units, available in public areas. Two metrics are considered to evaluate the system's success: (i) user engagement, and (ii) used cooking oil collection efficiency. The presented system should (i) perform under scenarios of temporary communication network failures, and (ii) be scalable to accommodate an ever-growing number of installed collection units. Thus, we choose a disruptive approach from the traditional cloud computing paradigm. It relies on edge node infrastructure to process, store, and act upon the locally collected data. The communication appears as a delay-tolerant task, i.e., an edge computing solution. We conduct a comparative analysis revealing the benefits of the edge computing enabled collection bin vs. a cloud computing solution. The studied period considers four years of collected data. An exponential increase in the amount of used cooking oil collected is identified, with the developed solution being responsible for surpassing the national collection totals of previous years. During the same period, we also improved the collection process as we were able to more accurately estimate the optimal collection and system's maintenance intervals.

17.
Nano Lett ; 23(3): 850-857, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36689916

RESUMEN

Magnetic nanorods driven by rotating fields in water can be rapidly steered along any direction while generating strong and localized hydrodynamic flow fields. Here we show that, when raising the frequency of the rotating field, these nanopropellers undergo a dynamic transition from a rolling to a kayak-like motion due to the increase in viscous drag and acquire a finite inclination angle with respect to the plane perpendicular to the bottom surface. We explain these experimental observations with a theoretical model which considers the nanorod as a pair of ferromagnetic particles hydrodynamically interacting with a close stationary surface. Further, we quantify how efficiently microscopic cargoes can be trapped or expelled from the moving nanorod and use numerical simulations to unveil the generated hydrodynamic flow field. These propulsion regimes can be implemented in microfluidic devices to perform precise operations based on the selective sorting of microscopic cargoes.

18.
J Stroke Cerebrovasc Dis ; : 107830, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38909872

RESUMEN

OBJECTIVES: The objective of this study was to determine factors associated with negative disease-related stigma after hemorrhagic stroke. MATERIALS AND METHODS: Patients with non-traumatic hemorrhage (ICH or SAH) admitted between January 2015 and February 2021 were assessed by telephone 3-months after discharge using the Quality of Life in Neurological Disorders (Neuro-QoL) Negative Disease-Related Stigma Short Form inventory. We evaluated the relationship between disease-related stigma (T-score>50) and pre-stroke demographics, admission data, and poor functional outcome (3-month mRS score 3-5 and Barthel Index <100). RESULTS: We included 89 patients (56 ICH and 33 SAH). The median age was 63 (IQR 50-69), 43% were female, and 67% graduated college. Admission median GCS score was 15 (IQR 13-15) and APACHE II score was 12 (IQR 9-17). 31% had disease-related stigma. On univariate analysis, disease-related stigma was associated with female sex, non-completion of college, GCS score, APACHE II score, and 3-month mRS score (all p<0.05). On multivariate analysis, disease-related stigma was associated with female sex (OR = 3.72, 95% CI = 1.23-11.25, p = 0.02) and 3-month Barthel Index<100 (OR = 3.46, 95% CI = 1.13-10.64, p = 0.03) on one model, and female sex (OR = 3.75, 95% CI = 1.21-11.58, p = 0.02) and 3-month mRS score 3-5 (OR = 4.23, 95% CI = 1.21-14.75, p = 0.02) on a second model. CONCLUSION: Functional outcome and female sex are associated with disease-related stigma 3-months after hemorrhagic stroke. Because stigma may negatively affect recovery, there is a need to understand the relationship between these factors to mitigate stroke-related stigma.

19.
Artículo en Inglés | MEDLINE | ID: mdl-38351838

RESUMEN

Although coronary angiography (CA) is the gold standard for coronary allograft vasculopathy (CAV) screening, non-invasive modalities have arisen as potential alternatives, such as coronary computed tomography angiography (CCTA). CCTA also quantifies plaque burden, which may influence medical treatment. From January 2021 to April 2022, we prospectively included heart transplant recipients who performed CCTA as a first-line method for CAV detection in a single center. Clinical, CCTA, and CA data were collected. 38 patients were included, 60.5% men, aged 58±14 years. The most frequent cause of transplantation was dilated cardiomyopathy (42.1%), and the median graft duration was 10 years [interquartile range (IQR) 9]. The median left ventricle ejection fraction was 61.5% (IQR 6). The median calcium score was 17 (IQR 231) and 32 patients (84.2%) proceeded to CCTA: 7, 24, and 1 patients had a graded CAV of 0, 1, and 2, respectively. Most patients (37.5%) had both calcified and non-calcified plaques, and the median number of affected segments was 2 (IQR 3). The remaining six patients had extensive coronary calcification, so CA was performed: 4 had CAV1, 1 had CAV2, and 1 had CAV3. During follow-up (12.2±4.2 months), there were neither deaths nor acute coronary syndromes. After CCTA, therapeutic changes occurred in about 10 (26.3%) of patients, mainly related to anti-lipid intensification; such changes were more frequent in patients with diabetes after heart transplant. In this cohort, CCTA led to therapeutic changes in about one-quarter of patients; more studies are needed to assess how CCT may guide therapy according to plaque burden.

20.
Rev Esp Enferm Dig ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38685905

RESUMEN

Following the growing trend of trying to individualise treatment in inflammatory bowel disease and in view of the challenge posed by elderly patients requiring biologic treatments, we have conducted a study in our centre to assess the T3/T4 index as a predictor of response to biologic treatments in elderly patients.

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