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Kinesin and dynein are opposite-polarity microtubule motors that drive the tightly regulated transport of a variety of cargoes. Both motors can bind to cargo, but their overall composition on axonal vesicles and whether this composition directly modulates transport activity are unknown. Here we characterize the intracellular transport and steady-state motor subunit composition of mammalian prion protein (PrP(C)) vesicles. We identify Kinesin-1 and cytoplasmic dynein as major PrP(C) vesicle motor complexes and show that their activities are tightly coupled. Regulation of normal retrograde transport by Kinesin-1 is independent of dynein-vesicle attachment and requires the vesicle association of a complete Kinesin-1 heavy and light chain holoenzyme. Furthermore, motor subunits remain stably associated with stationary as well as with moving vesicles. Our data suggest a coordination model wherein PrP(C) vesicles maintain a stable population of associated motors whose activity is modulated by regulatory factors instead of by structural changes to motor-cargo associations.
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Axones/metabolismo , Dineínas/metabolismo , Cinesinas/metabolismo , Proteínas PrPC/metabolismo , Animales , Hipocampo/metabolismo , Ratones , Ratones Endogámicos C57BL , Actividad Motora , Neuronas/metabolismo , Vesículas Transportadoras/metabolismoRESUMEN
Ageing is the most prominent risk for osteoarthritis (OA) development. This study aimed to investigate the role of phosphoinositide-specific phospholipase Cγ (PLCγ) 1, previously linked to OA progression, in regulating age-related changes in articular cartilage and subchondral bone. d-galactose (d-Gal) was employed to treat chondrocytes from rats and mice or injected intraperitoneally into C57BL/6 mice. RTCA, qPCR, Western blot and immunohistochemistry assays were used to evaluate cell proliferation, matrix synthesis, senescence genes and senescence-associated secretory phenotype, along with PLCγ1 expression. Subchondral bone morphology was assessed through micro-CT. In mice with chondrocyte-specific Plcg1 deficiency (Plcg1flox/flox; Col2a1-CreERT), articular cartilage and subchondral bone were examined over different survival periods. Our results showed that d-Gal induced chondrocyte senescence, expedited articular cartilage ageing and caused subchondral bone abnormalities. In d-Gal-induced chondrocytes, diminished PLCγ1 expression was observed, and its further inhibition by U73122 exacerbated chondrocyte senescence. Plcg1flox/flox; Col2a1-CreERT mice exhibited more pronounced age-related changes in articular cartilage and subchondral bone compared to Plcg1flox/flox mice. Therefore, not only does d-Gal induce senescence in chondrocytes and age-related changes in articular cartilage and subchondral bone, as well as diminished PLCγ1 expression, but PLCγ1 deficiency in chondrocytes may also accelerate age-related changes in articular cartilage and subchondral bone. PLCγ1 may be a promising therapeutic target for mitigating age-related changes in joint tissue.
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Cartílago Articular , Condrocitos , Ratones Endogámicos C57BL , Fosfolipasa C gamma , Animales , Condrocitos/metabolismo , Fosfolipasa C gamma/metabolismo , Fosfolipasa C gamma/genética , Cartílago Articular/metabolismo , Cartílago Articular/patología , Ratones , Envejecimiento/metabolismo , Osteoartritis/patología , Osteoartritis/metabolismo , Osteoartritis/genética , Osteoartritis/etiología , Senescencia Celular , Ratas , Estrenos/farmacología , Galactosa/metabolismo , Proliferación Celular , Masculino , Huesos/metabolismo , Huesos/patología , Huesos/diagnóstico por imagen , Pirrolidinonas/farmacologíaRESUMEN
OBJECTIVES: To explore the use of deep learning-constrained compressed sensing (DLCS) in improving image quality and acquisition time for 3D MRI of the brachial plexus. METHODS: Fifty-four participants who underwent contrast-enhanced imaging and forty-one participants who underwent unenhanced imaging were included. Sensitivity encoding with an acceleration of 2 × 2 (SENSE4x), CS with an acceleration of 4 (CS4x), and DLCS with acceleration of 4 (DLCS4x) and 8 (DLCS8x) were used for MRI of the brachial plexus. Apparent signal-to-noise ratios (aSNRs), apparent contrast-to-noise ratios (aCNRs), and qualitative scores on a 4-point scale were evaluated and compared by ANOVA and the Friedman test. Interobserver agreement was evaluated by calculating the intraclass correlation coefficients. RESULTS: DLCS4x achieved higher aSNR and aCNR than SENSE4x, CS4x, and DLCS8x (all p < 0.05). For the root segment of the brachial plexus, no statistically significant differences in the qualitative scores were found among the four sequences. For the trunk segment, DLCS4x had higher scores than SENSE4x (p = 0.04) in the contrast-enhanced group and had higher scores than SENSE4x and DLCS8x in the unenhanced group (all p < 0.05). For the divisions, cords, and branches, DLCS4x had higher scores than SENSE4x, CS4x, and DLCS8x (all p ≤ 0.01). No overt difference was found among SENSE4x, CS4x, and DLCS8x in any segment of the brachial plexus (all p > 0.05). CONCLUSIONS: In three-dimensional MRI for the brachial plexus, DLCS4x can improve image quality compared with SENSE4x and CS4x, and DLCS8x can maintain the image quality compared to SENSE4x and CS4x. CLINICAL RELEVANCE STATEMENT: Deep learning-constrained compressed sensing can improve the image quality or accelerate acquisition of 3D MRI of the brachial plexus, which should be benefit in evaluating the brachial plexus and its branches in clinical practice. KEY POINTS: â¢Deep learning-constrained compressed sensing showed higher aSNR, aCNR, and qualitative scores for the brachial plexus than SENSE and CS at the same acceleration factor with similar scanning time. â¢Deep learning-constrained compressed sensing at acceleration factor of 8 had comparable aSNR, aCNR, and qualitative scores to SENSE4x and CS4x with approximately half the examination time. â¢Deep learning-constrained compressed sensing may be helpful in clinical practice for improving image quality and acquisition time in three-dimensional MRI of the brachial plexus.
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Plexo Braquial , Aprendizaje Profundo , Humanos , Imagenología Tridimensional/métodos , Plexo Braquial/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Relación Señal-RuidoRESUMEN
Potato virus Y (PVY) is one of the most important pathogens in the genus Potyvirus that seriously harms agricultural production. Copper (Cu), as a micronutrient, is closely related to plant immune response. In this study, we found that foliar application of Cu could inhibit PVY infection to some extent, especially at 7 days post inoculation (dpi). To explore the effect of Cu on PVY infection, transcriptome sequencing analysis was performed on PVY-infected tobacco with or without Cu application. Several key pathways regulated by Cu were identified, including plant-pathogen interaction, inorganic ion transport and metabolism, and photosynthesis. Moreover, the results of virus-induced gene silencing (VIGS) assays revealed that NbMLP423, NbPIP2, NbFd and NbEXPA played positive roles in resistance to PVY infection in Nicotiana benthamiana. In addition, transgenic tobacco plants overexpressing NtEXPA11 showed increased resistance to PVY infection. These results contribute to clarify the role and regulatory mechanism of Cu against PVY infection, and provide candidate genes for disease resistance breeding.
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Cobre , Resistencia a la Enfermedad , Nicotiana , Enfermedades de las Plantas , Potyvirus , Nicotiana/virología , Nicotiana/genética , Potyvirus/fisiología , Cobre/farmacología , Enfermedades de las Plantas/virología , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilación de la Expresión Génica , Plantas Modificadas Genéticamente/virología , Regulación de la Expresión Génica de las Plantas , TranscriptomaRESUMEN
The aberrant activation of NLRP3 inflammasomes is intricately linked to various inflammatory diseases. In this study, we present the discovery and optimization of a series of NLRP3 inflammasome inhibitors based on the pterostilbene skeleton. All compounds underwent screening to evaluate their inhibitory effects on LPS/Nigericin-induced IL-1ß secretion and anti-cellular pyroptosis. Most compounds exhibit good biological activity and cellular safety, with compound D20 showing the most prominent activity. Preliminary mechanism studies suggest that compound D20 may affect the assembly of NLRP3 inflammasomes by targeting the NLRP3 protein, thereby inhibiting the activation of NLRP3 inflammasomes. The in vivo anti-inflammatory activity demonstrated significant therapeutic effect of compound D20 on DSS-induced acute colitis model in mice. This work has important reference significance for the development of drugs targeting NLRP3 inflammasomes.
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MOTIVATION: Coiled-coil is composed of two or more helices that are wound around each other. It widely exists in proteins and has been discovered to play a variety of critical roles in biology processes. Generally, there are three types of structural features in coiled-coil: coiled-coil domain (CCD), oligomeric state and register. However, most of the existing computational tools only focus on one of them. RESULTS: Here, we describe a new deep learning model, CoCoPRED, which is based on convolutional layers, bidirectional long short-term memory, and attention mechanism. It has three networks, i.e. CCD network, oligomeric state network, and register network, corresponding to the three types of structural features in coiled-coil. This means CoCoPRED has the ability of fulfilling comprehensive prediction for coiled-coil proteins. Through the 5-fold cross-validation experiment, we demonstrate that CoCoPRED can achieve better performance than the state-of-the-art models on both CCD prediction and oligomeric state prediction. Further analysis suggests the CCD prediction may be a performance indicator of the oligomeric state prediction in CoCoPRED. The attention heads in CoCoPRED indicate that registers a, b and e are more crucial for the oligomeric state prediction. AVAILABILITY AND IMPLEMENTATION: CoCoPRED is available at http://www.csbio.sjtu.edu.cn/bioinf/CoCoPRED. The datasets used in this research can also be downloaded from the website. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Redes Neurales de la Computación , Proteínas , Secuencia de Aminoácidos , Proteínas/química , Dominios Proteicos , Estructura Secundaria de ProteínaRESUMEN
Cartilaginous fish are the most primitive extant species with MHC molecules. Using the nurse shark, the current study is, to the best of our knowledge, the first to present a peptide-loaded MHC class I (pMHC-I) structure for this class of animals. The overall structure was found to be similar between cartilaginous fish and bony animals, showing remarkable conservation of interactions between the three pMHC-I components H chain, ß2-microglobulin (ß2-m), and peptide ligand. In most previous studies, relatively little attention was given to the details of binding between the H chain and ß2-m, and our study provides important new insights. A pronounced conserved feature involves the insertion of a large ß2-m F56+W60 hydrophobic knob into a pleat of the ß-sheet floor of the H chain α1α2 domain, with the knob being surrounded by conserved residues. Another conserved feature is a hydrogen bond between ß2-m Y10 and a proline in the α3 domain of the H chain. By alanine substitution analysis, we found that the conserved ß2-m residues Y10, D53, F56, and W60-each binding the H chain-are required for stable pMHC-I complex formation. For the ß2-m residues Y10 and F56, such observations have not been reported before. The combined data indicate that for stable pMHC-I complex formation ß2-m should not only bind the α1α2 domain but also the α3 domain. Knowing the conserved structural features of pMHC-I should be helpful for future elucidations of the mechanisms of pMHC-I complex formation and peptide editing.
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Antígenos de Histocompatibilidad Clase I/inmunología , Péptidos/inmunología , Microglobulina beta-2/inmunología , Animales , Antígenos de Histocompatibilidad Clase I/química , Péptidos/química , Unión Proteica , Conformación Proteica , TiburonesRESUMEN
The reptile MHC class I (MCH-I) and MHC class II proteins are the key molecules in the immune system; however, their structure has not been investigated. The crystal structure of green anole lizard peptide-MHC-I-ß2m (pMHC-I or pAnca-UA*0101) was determined in the current study. Subsequently, the features of pAnca-UA*0101 were analyzed and compared with the characteristics of pMHC-I of four classes of vertebrates. The amino acid sequence identities between Anca-UA*0101 and MHC-I from other species are <50%; however, the differences between the species were reflected in the topological structure. Significant characteristics of pAnca-UA*0101 include a specific flip of â¼88° and an upward shift adjacent to the C terminus of the α1- and α2-helical regions, respectively. Additionally, the lizard MHC-I molecule has an insertion of 2 aa (VE) at positions 55 and 56. The pushing force from 55-56VE triggers the flip of the α1 helix. Mutagenesis experiments confirmed that the 55-56VE insertion in the α1 helix enhances the stability of pAnca-UA*0101. The peptide presentation profile and motif of pAnca-UA*0101 were confirmed. Based on these results, the proteins of three reptile lizard viruses were used for the screening and confirmation of the candidate epitopes. These data enhance our understanding of the systematic differences between five classes of vertebrates at the gene and protein levels, the formation of the pMHC-I complex, and the evolution of the MHC-I system.
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Antígenos de Histocompatibilidad Clase I/química , Lagartos/inmunología , Infecciones por Nidovirales/inmunología , Nidovirales/fisiología , Proteínas de Reptiles/química , Secuencia de Aminoácidos , Animales , Antígenos Virales/genética , Cristalografía por Rayos X , Epítopos/genética , Evolución Molecular , Antígenos de Histocompatibilidad Clase I/genética , Sistema Inmunológico , Inmunidad , Filogenia , Polimorfismo Genético , Conformación Proteica , Estabilidad Proteica , Proteínas de Reptiles/genéticaRESUMEN
BACKGROUND: Medical care avoidance affects individuals' health status. Previous studies on medical care avoidance have mainly focused on medical costs and people's satisfaction with medical services. This study investigates whether an individual's sense of policy alienation toward medical care policy (SPA-M) affects behavioral intention of medical care avoidance, and to what extent an intermediary variable-medical financial risk perception-mediates the relationship between SPA-M and medical care avoidance. METHODS: A cross-sectional survey was conducted involving 434 people aged 35-59 years from Wuhu, a city in China's Anhui province. A moderated mediation model was constructed to investigate the research question and sex (biological: male and female) was used as a moderating variable between SPA-M and medical financial risk perception. RESULTS: We found that SPA-M significantly impacted medical care avoidance, and that medical financial risk perception played a complete mediating role in this relationship, while sex moderated the relationship between SPA-M and medical financial risk perception. CONCLUSION: This study contributes to the literature by enhancing our understanding of the factors that influence behavioral intention regarding medical care avoidance, deepening our understanding of the role of SPA-M in medical care policy, and expanding the role of sex differences in the analysis of the relationship between SPA-M, medical financial risk perception, and medical care avoidance, offering implications for public and community health.
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Emociones , Intención , Humanos , Masculino , Femenino , Estudios Transversales , Políticas , PercepciónRESUMEN
Knowledge of the interactions between proteins and nucleic acids is the basis of understanding various biological activities and designing new drugs. How to accurately identify the nucleic-acid-binding residues remains a challenging task. In this paper, we propose an accurate predictor, GraphBind, for identifying nucleic-acid-binding residues on proteins based on an end-to-end graph neural network. Considering that binding sites often behave in highly conservative patterns on local tertiary structures, we first construct graphs based on the structural contexts of target residues and their spatial neighborhood. Then, hierarchical graph neural networks (HGNNs) are used to embed the latent local patterns of structural and bio-physicochemical characteristics for binding residue recognition. We comprehensively evaluate GraphBind on DNA/RNA benchmark datasets. The results demonstrate the superior performance of GraphBind than state-of-the-art methods. Moreover, GraphBind is extended to other ligand-binding residue prediction to verify its generalization capability. Web server of GraphBind is freely available at http://www.csbio.sjtu.edu.cn/bioinf/GraphBind/.
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Proteínas de Unión al ADN/química , Redes Neurales de la Computación , Proteínas de Unión al ARN/química , Sitios de Unión , ADN/química , Unión Proteica , Conformación Proteica , ARN/química , Programas InformáticosRESUMEN
We aimed to clarify whether health literacy (HL) impacts medical care avoidance through an underexplored mediator: a sense of policy alienation towards medical care policy for residents (SPA-M). A moderated mediation model with control perception as a moderator was used to analyze the inner relationship between HL and SPA-M. A cross-sectional survey of 470 people ≥ 60 years old, revealed a significant negative association between HL and medical care avoidance intention, which bootstrapped moderated mediation analysis confirmed is partially mediated by SPA-M. When older people's control perception was high, HL had a significant negative impact on medical care avoidance intention through SPA-M; for low control perception, the effect was insignificant. This study elucidates HL's impact of HL on medical care avoidance, highlighting control perception's relevance to medical care policymaking for older people.
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Alfabetización en Salud , Humanos , Anciano , Estudios Transversales , Emociones , Encuestas y CuestionariosRESUMEN
Astrocytes are the most common glial type in the central nervous system. They play pivotal roles in neurophysiological and neuropathological processes. Mounting evidence indicates that astrocytes may act as neural stem cells and contribute to adult neurogenesis. In previous reports, freshly isolated O-2A progenitors were shown to revert to neural stem-like cells (NSLCs) when cultured with a serum-containing glial medium or bone morphogenic proteins for 3 days and with basic fibroblast growth factor consecutively. NSLCs possess self-renewal and multipotential capacities that can give rise to neurons and glial cells, which suggests that they have stem cell-like properties. However, the underlying molecular mechanisms and cell fate commitment when exposed to a neural conditioned medium remain obscure. In this study, we demonstrated that NSLCs grown in the serum-containing neurobasal medium can differentiate into induced neural-like cells (iNLCs). It was noteworthy that astroglia mixed in these cells, particularly in iNLCs, were gradually replaced by neural phenotypes during this glia-neuron conversion. Remarkably, these glial cells can maintain high levels of proliferation and self-renewal ability by activating the NF-κB and MAPK signals. Finally, we found that Notch, STAT3, autophagy, bHLH, and Wnt signals appear to be critical modulators of these intricate events. Altogether, these data demonstrate that O-2A lineage astroglia can function as neural stem cells and display neurogenic plasticity. Dissecting the regulatory pathways involved in these processes is essential to the understanding of glial cell fate and its precise functions. This finding may foster a better understanding of astrocytic heterogeneity and lead to innovative ways to readily apply stem-like astroglia cells as candidate cell sources for neural repair.
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Astrocitos , Células-Madre Neurales , Oligodendroglía/metabolismo , Neuroglía , Diferenciación Celular , Linaje de la CélulaRESUMEN
Photonic crystals can be engineered so that the flow of optical power and the phase of the field are independently controlled. The concept is demonstrated by creating a self-collimating lattice with an embedded cylindrical lens. The device is fabricated in a photopolymer by multi-photon lithography with the lattice spacing chosen for operation around the telecom wavelength of 1550 nm. The lattice is based on a low-symmetry rod-in-wall unit cell that strongly self-collimates light. The walls are varied in thickness to modulate the effective refractive index so light acquires a spatially quadratic phase profile as it propagates through the device. Although the phase of the field is altered, the light does not focus within the device because self-collimation forces power to flow parallel to the principal axes of the lattice. Upon exiting the device, ordinary propagation resumes in free space and the curved phase profile causes the light to focus. An analysis of the experimentally observed optical behavior shows that the device behaves like a thin lens, even though the device is considerably thick.
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A binary-lens-embedded photonic crystal (B-LEPC) was designed for operation at 1550â nm and fabricated by multiphoton lithography. The lens is binary in the sense that optical path difference is generated using unit cells having just two distinct fill factors. The unit cells have a "rod-in-wall" structure that exhibits three-dimensional self-collimation. Simulations show that self-collimation forces light to move through the device without diffracting or focusing, even as the wavefront is reshaped by the lensing region. Upon exiting the device, the curved wavefront causes the light to focus. The thickness of a B-LEPC was reduced threefold by wrapping phase in the style of a Fresnel lens. Embedding a faster-varying phase profile enables tighter focusing, and numerical aperture NA = 0.59 was demonstrated experimentally.
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BACKGROUND: The majority of heart failure (HF) in hypertrophic cardiomyopathy (HCM) manifests as a phenotype with preserved left ventricular (LV) ejection fraction; however, the exact contribution of left atrial (LA) phasic function to HF with preserved ejection fraction (HFpEF) in HCM remains unresolved. PURPOSE: To define the association between LA function and HFpEF in HCM patients using cardiac magnetic resonance imaging (MRI) feature tracking. STUDY TYPE: Retrospective. POPULATION: One hundred and fifty-four HCM patients (HFpEF vs. non-HF: 55 [34 females] vs. 99 [43 females]). FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession. ASSESSMENT: LA reservoir function (reservoir strain [εs ], total ejection fraction [EF]), conduit function (conduit strain [εe ], passive EF), booster-pump function (booster strain [εa ] and active EF), LA volume index, and LV global longitudinal strain (LV GLS) were evaluated in HCM patients. STATISTICAL TESTS: Chi-square test, Student's t-test, Mann-Whitney U test, multivariate linear regression, logistic regression, and net reclassification analysis were used. Two-sided P < 0.05 was considered statistically significant. RESULTS: No significant difference was found in LV GLS between the non-HF and HFpEF group (-10.67 ± 3.14% vs. -10.14 ± 4.01%, P = 0.397), whereas the HFpEF group had more severely impaired LA phasic strain (εs : 27.40 [22.60, 35.80] vs. 18.15 [11.98, 25.90]; εe : 13.80 [9.20, 18.90] vs. 7.95 [4.30, 14.35]; εa : 13.50 [9.90, 17.10] vs. 7.90 [5.40, 14.15]). LA total EF (37.91 [29.54, 47.94] vs. 47.49 [39.18, 55.01]), passive EF (14.70 [7.41, 21.49] vs. 18.07 [9.32, 24.78]), and active EF (27.19 [17.79, 36.60] vs. 36.64 [26.63, 42.71]) were all significantly decreased in HFpEF patients compared with non-HF patients. LA reservoir (ß = 0.90 [0.85, 0.96]), conduit (ß = 0.93 [0.87, 0.99]), and booster (ß = 0.86 [0.78, 0.95]) strain were independently associated with HFpEF in HCM patients. The model including reservoir strain (Net Reclassification Index [NRI]: 0.260) or booster strain (NRI: 0.325) improved the reclassification of HFpEF based on LV GLS and minimum left atrial volume index (LAVImin ). DATA CONCLUSION: LA phasic function was severely impaired in HCM patients with HFpEF, whereas LV function was not further impaired compared with non-HF patients. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.
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Cardiomiopatía Hipertrófica , Insuficiencia Cardíaca , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Estudios de Casos y Controles , Femenino , Atrios Cardíacos/diagnóstico por imagen , Insuficiencia Cardíaca/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
OBJECTIVES: To investigate the feasibility of automatic machine learning (autoML) based on native T1 mapping to predict late gadolinium enhancement (LGE) status in hypertrophic cardiomyopathy (HCM). METHODS: Ninety-one HCM patients and 44 healthy controls who underwent cardiovascular MRI were enrolled. The native T1 maps of HCM patients were classified as LGE ( +) or LGE (-) based on location-matched LGE images. An autoML pipeline was implemented using the tree-based pipeline optimization tool (TPOT) for 3 binary classifications: LGE ( +) and LGE (-), LGE (-) and control, and HCM and control. TPOT modeling was repeated 10 times to obtain the optimal model for each classification. The diagnostic performance of the best models by slice and by case was evaluated using sensitivity, specificity, accuracy, and microaveraged area under the curve (AUC). RESULTS: Ten prediction models were generated by TPOT for each of the 3 binary classifications. The diagnostic accuracy obtained with the best pipeline in detecting LGE status in the testing cohort of HCM patients was 0.80 by slice and 0.79 by case. In addition, the TPOT model also showed discriminability between LGE (-) patients and control (accuracy: 0.77 by slice; 0.78 by case) and for all HCM patients and controls (accuracy: 0.88 for both). CONCLUSIONS: Native T1 map analysis based on autoML correlates with LGE ( +) or (-) status. The TPOT machine learning algorithm could be a promising method for predicting myocardial fibrosis, as reflected by the presence of LGE in HCM patients without the need for late contrast-enhanced MRI sequences. KEY POINTS: ⢠The tree-based pipeline optimization tool (TPOT) is a machine learning algorithm that could help predict late gadolinium enhancement (LGE) status in patients with hypertrophic cardiomyopathy. ⢠The TPOT could serve as an adjuvant method to detect LGE by using information from native T1 maps, thus avoiding the need for contrast agent. ⢠The TPOT also detects native T1 map alterations in LGE-negative patients with hypertrophic cardiomyopathy.
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Cardiomiopatía Hipertrófica , Medios de Contraste , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Fibrosis , Gadolinio , Humanos , Aprendizaje Automático , Imagen por Resonancia Cinemagnética , Miocardio/patologíaRESUMEN
OBJECTIVES: We aimed to evaluate myocardial fibrosis using cardiac magnetic resonance (CMR) T1 mapping in type 2 diabetes mellitus (T2DM) patients and investigate the association between left ventricular (LV) subclinical myocardial dysfunction and myocardial fibrosis. METHODS: The study included 37 short-term (≤ 5 years) and 44 longer-term (> 5 years) T2DM patients and 41 healthy controls. The LV global strain parameters and T1 mapping parameters were compared between the abovementioned three groups. The association of T1 mapping parameters with diabetes duration, in addition to other risk factors, was determined using multivariate linear regression analysis. The correlation between LV strain parameters and T1 mapping parameters was evaluated using Pearson's correlation. RESULTS: The peak diastolic strain rates (PDSRs) were significantly lower in longer-term T2DM patients compared to those in healthy subjects and short-term T2DM patients (p < 0.05). The longitudinal peak systolic strain rate and peak strain were significantly lower in the longer-term T2DM compared with the short-term T2DM group (p < 0.05). The extracellular volumes (ECVs) were higher in both subgroups of T2DM patients compared with control subjects (all p < 0.05). Multivariate linear regression analysis showed that diabetes duration was independently associated with ECV (ß = 0.413, p < 0.001) by taking covariates into account. Pearson's analysis showed that ECV was associated with longitudinal PDSR (r = - 0.441, p < 0.001). CONCLUSION: T1 mapping could detect abnormal myocardial fibrosis early in patients with T2DM, which can cause a decline in the LV diastolic function. KEY POINTS: ⢠CMR T1 mapping could detect abnormal myocardial fibrosis early in patients with T2DM. ⢠The diabetes duration was independently associated with ECV. ⢠Myocardial fibrosis can cause a decline in the LV diastolic function in T2DM patients.
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Cardiomiopatías , Diabetes Mellitus Tipo 2 , Disfunción Ventricular Izquierda , Humanos , Diabetes Mellitus Tipo 2/patología , Imagen por Resonancia Cinemagnética/efectos adversos , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular Izquierda , Miocardio/patología , Fibrosis , Espectroscopía de Resonancia Magnética , Valor Predictivo de las PruebasRESUMEN
The goal of limiting global warming to 1.5 °C requires a drastic reduction in CO2 emissions across many sectors of the world economy. Batteries are vital to this endeavor, whether used in electric vehicles, to store renewable electricity, or in aviation. Present lithium-ion technologies are preparing the public for this inevitable change, but their maximum theoretical specific capacity presents a limitation. Their high cost is another concern for commercial viability. Metal-air batteries have the highest theoretical energy density of all possible secondary battery technologies and could yield step changes in energy storage, if their practical difficulties could be overcome. The scope of this review is to provide an objective, comprehensive, and authoritative assessment of the intensive work invested in nonaqueous rechargeable metal-air batteries over the past few years, which identified the key problems and guides directions to solve them. We focus primarily on the challenges and outlook for Li-O2 cells but include Na-O2, K-O2, and Mg-O2 cells for comparison. Our review highlights the interdisciplinary nature of this field that involves a combination of materials chemistry, electrochemistry, computation, microscopy, spectroscopy, and surface science. The mechanisms of O2 reduction and evolution are considered in the light of recent findings, along with developments in positive and negative electrodes, electrolytes, electrocatalysis on surfaces and in solution, and the degradative effect of singlet oxygen, which is typically formed in Li-O2 cells.
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MHC class II (MHC-II) molecules play a crucial role in cellular and humoral immunity by forming peptide-MHC-II (pMHC-II) complexes. The three-dimensional structures of pMHC-II complexes have been well resolved in humans and mice. However, there is no structural information for pMHC-II complexes in nonmammals. In chickens, there are two closely related and highly polymorphic ß-chains and one monomorphic α-chain, and the mechanism by which one monomorphic α-chain combines with two polymorphic ß-chains to form a functional heterodimer remains unknown. In this study, we report the crystal structure of a chicken pMHC-II complex (pBL2*019:01) at 1.9-Å resolution as the first nonmammalian structure of a pMHC-II complex. The structure reveals an increase in hydrogen bonding between the α and ß main chains at the central interface that is introduced by the insertion of four residues in the α-chain. The residues in the ß-chain that form hydrogen bonds with the α-chain are conserved among all ß alleles. These structural characteristics explain the phenomenon of only one BLA allele without sequence variation pairing with highly diverse BLB alleles from two loci in the genome. Additionally, the characteristics of the peptide in the peptide-binding groove were confirmed. These results provide a new understanding of the pairing mechanism of the α- and ß-chains in a pMHC-II complex and establish a structural principle to design epitope-related vaccines for the prevention of chicken diseases.
Asunto(s)
Pollos/inmunología , Genes MHC Clase II/genética , Antígenos de Histocompatibilidad Clase II/ultraestructura , Multimerización de Proteína/inmunología , Estructura Cuaternaria de Proteína , Animales , Presentación de Antígeno/inmunología , Pollos/genética , Cristalografía por Rayos X , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , Evolución Molecular , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase II/inmunología , Dominios Proteicos/genética , Dominios Proteicos/inmunología , Multimerización de Proteína/genéticaRESUMEN
A 16-year-old male was admitted to the hospital for weakness of both lower extremities. Magnetic resonance imaging revealed an intraspinal extramedullary subdural mass at the thoracic 9 level. Microscopically, the tumor cells were small to medium sized and round to ovoid in shape. They were distributed in diffuse sheets or showed nodular appearance. The nucleus of the tumor had mild-to-moderate atypia, with vesicular chromatin and prominent nucleoli. A smaller proportion of tumor cells demonstrated rhabdoid morphology. Focal myxoid stromal change was present, in which tumor cells exhibited spindle shapes. Approximately two mitoses were counted per 10 high-power fields. No necrosis was observed. The tumor cells were focal positive for CD99; multifocal positive for WT1; diffuse positive for nestin, synaptophysin, and D2-40; partial positive for GFAP; focal positive for desmin and SSTR2; and scattered positive for S-100 protein. The Ki-67 labeling index was approximately 20%. Genetic testing revealed CIC-LEUTX gene fusion. Considering the patient's history, clinical data, pathological findings and genetic findings, we rendered a rare tumor named CIC-rearranged sarcoma with CIC-LEUTX gene fusion.