Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 555
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Nature ; 616(7955): 176-182, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36991118

RESUMEN

Repression of gene expression by protein complexes of the Polycomb group is a fundamental mechanism that governs embryonic development and cell-type specification1-3. The Polycomb repressive deubiquitinase (PR-DUB) complex removes the ubiquitin moiety from monoubiquitinated histone H2A K119 (H2AK119ub1) on the nucleosome4, counteracting the ubiquitin E3 ligase activity of Polycomb repressive complex 1 (PRC1)5 to facilitate the correct silencing of genes by Polycomb proteins and safeguard active genes from inadvertent silencing by PRC1 (refs. 6-9). The intricate biological function of PR-DUB requires accurate targeting of H2AK119ub1, but PR-DUB can deubiquitinate monoubiquitinated free histones and peptide substrates indiscriminately; the basis for its exquisite nucleosome-dependent substrate specificity therefore remains unclear. Here we report the cryo-electron microscopy structure of human PR-DUB, composed of BAP1 and ASXL1, in complex with the chromatosome. We find that ASXL1 directs the binding of the positively charged C-terminal extension of BAP1 to nucleosomal DNA and histones H3-H4 near the dyad, an addition to its role in forming the ubiquitin-binding cleft. Furthermore, a conserved loop segment of the catalytic domain of BAP1 is situated near the H2A-H2B acidic patch. This distinct nucleosome-binding mode displaces the C-terminal tail of H2A from the nucleosome surface, and endows PR-DUB with the specificity for H2AK119ub1.


Asunto(s)
Enzimas Desubicuitinizantes , Histonas , Complejo Represivo Polycomb 1 , Proteínas del Grupo Polycomb , Humanos , Microscopía por Crioelectrón , Histonas/química , Histonas/metabolismo , Nucleosomas/química , Nucleosomas/genética , Nucleosomas/metabolismo , Complejo Represivo Polycomb 1/química , Complejo Represivo Polycomb 1/metabolismo , Complejo Represivo Polycomb 1/ultraestructura , Proteínas del Grupo Polycomb/química , Proteínas del Grupo Polycomb/metabolismo , Proteínas del Grupo Polycomb/ultraestructura , Ubiquitina/metabolismo , Ubiquitina Tiolesterasa/química , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina Tiolesterasa/ultraestructura , Ubiquitinación , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Proteínas Represoras/ultraestructura , Dominio Catalítico , Enzimas Desubicuitinizantes/clasificación , Enzimas Desubicuitinizantes/metabolismo , Enzimas Desubicuitinizantes/ultraestructura , Especificidad por Sustrato , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/ultraestructura
2.
Development ; 149(12)2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35588208

RESUMEN

As one of the post-transcriptional regulatory mechanisms, uncoupling of transcription and translation plays an essential role in development and adulthood physiology. However, it remains elusive how thousands of mRNAs get translationally silenced while stability is maintained for hours or even days before translation. In addition to oocytes and neurons, developing spermatids display significant uncoupling of transcription and translation for delayed translation. Therefore, spermiogenesis represents an excellent in vivo model for investigating the mechanism underlying uncoupled transcription and translation. Through full-length poly(A) deep sequencing, we discovered dynamic changes in poly(A) length through deadenylation and re-polyadenylation. Deadenylation appeared to be mediated by microRNAs (miRNAs), and transcripts with shorter poly(A) tails tend to be sequestered into ribonucleoprotein (RNP) granules for translational repression and stabilization. In contrast, re-polyadenylation might allow for translocation of the translationally repressed transcripts from RNP granules to polysomes. Overall, our data suggest that miRNA-dependent poly(A) length control represents a previously unreported mechanism underlying uncoupled translation and transcription in haploid male mouse germ cells.


Asunto(s)
MicroARNs , Poli A , Animales , Haploidia , Masculino , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Poli A/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Espermátides/metabolismo
3.
Nano Lett ; 24(8): 2544-2552, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38349341

RESUMEN

Labeling the genome and envelope of a virus with multicolor quantum dots (QDs) simultaneously enables real-time monitoring of viral uncoating and genome release, contributing to our understanding of virus infection mechanisms. However, current labeling techniques require genetic modification, which alters the virus's composition and infectivity. To address this, we utilized the CRISPR/Cas13 system and a bioorthogonal metabolic method to label the Japanese encephalitis virus (JEV) genome and envelopes with different-colored QDs in situ. This technique allows one-step two-color labeling of the viral envelope and intraviral genome with QDs harnessing virus infection. In combination with single-virus tracking, we visualized JEV uncoating and genome release in real time near the endoplasmic reticulum of live cells. This labeling strategy allows for real-time visualization of uncoating and genome release at the single-virus level, and it is expected to advance the study of other viral infection mechanisms.


Asunto(s)
Puntos Cuánticos , Virosis , Virus , Humanos , Envoltura Viral/metabolismo , Proteínas del Envoltorio Viral
4.
J Biol Chem ; 299(6): 104808, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37172719

RESUMEN

ELKS proteins play a key role in organizing intracellular vesicle trafficking and targeting in both neurons and non-neuronal cells. While it is known that ELKS interacts with the vesicular traffic regulator, the Rab6 GTPase, the molecular basis governing ELKS-mediated trafficking of Rab6-coated vesicles, has remained unclear. In this study, we solved the Rab6B structure in complex with the Rab6-binding domain of ELKS1, revealing that a C-terminal segment of ELKS1 forms a helical hairpin to recognize Rab6B through a unique binding mode. We further showed that liquid-liquid phase separation (LLPS) of ELKS1 allows it to compete with other Rab6 effectors for binding to Rab6B and accumulate Rab6B-coated liposomes to the protein condensate formed by ELKS1. We also found that the ELKS1 condensate recruits Rab6B-coated vesicles to vesicle-releasing sites and promotes vesicle exocytosis. Together, our structural, biochemical, and cellular analyses suggest that ELKS1, via the LLPS-enhanced interaction with Rab6, captures Rab6-coated vesicles from the cargo transport machine for efficient vesicle release at exocytotic sites. These findings shed new light on the understanding of spatiotemporal regulation of vesicle trafficking through the interplay between membranous structures and membraneless condensates.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Vesículas Cubiertas , Proteínas del Tejido Nervioso , Proteínas de Unión al GTP rab , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Vesículas Cubiertas/química , Vesículas Cubiertas/metabolismo , Exocitosis , Liposomas , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Neuronas/citología , Neuronas/metabolismo , Proteínas de Unión al GTP rab/química , Proteínas de Unión al GTP rab/metabolismo
5.
J Cell Physiol ; 239(3): e31027, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37099691

RESUMEN

Pulmonary fibrosis is a chronic and serious interstitial lung disease with little effective therapies currently. Our incomplete understanding of its pathogenesis remains obstacles in therapeutic developments. Sirtuin 6 (SIRT6) has been shown to mitigate multiple organic fibrosis. However, the involvement of SIRT6-mediated metabolic regulation in pulmonary fibrosis remains unclear. Here, we demonstrated that SIRT6 was predominantly expressed in alveolar epithelial cells in human lung tissues by using a single-cell sequencing database. We showed that SIRT6 protected against bleomycin-induced injury of alveolar epithelial cells in vitro and pulmonary fibrosis of mice in vivo. High-throughput sequencing revealed enriched lipid catabolism in Sirt6 overexpressed lung tissues. Mechanismly, SIRT6 ameliorates bleomycin-induced ectopic lipotoxicity by enhancing lipid degradation, thereby increasing the energy supply and reducing the levels of lipid peroxides. Furthermore, we found that peroxisome proliferator-activated receptor α (PPARα) was essential for SIRT6-mediated lipid catabolism, anti-inflammatory responses, and antifibrotic signaling. Our data suggest that targeting SIRT6-PPARα-mediated lipid catabolism could be a potential therapeutic strategy for diseases complicated with pulmonary fibrosis.


Asunto(s)
Metabolismo de los Lípidos , Fibrosis Pulmonar , Sirtuinas , Animales , Humanos , Ratones , Bleomicina , PPAR alfa/genética , PPAR alfa/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/metabolismo , Sirtuinas/genética , Sirtuinas/metabolismo
6.
BMC Cancer ; 24(1): 1073, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215210

RESUMEN

BACKGROUND & AIMS: Perilipin 1 (PLIN1) is an essential lipid droplet surface protein that participates in cell life activities by regulating energy balance and lipid metabolism. PLIN1 has been shown to be closely related to the development of numerous tumor types. The purpose of this work was to elucidate the clinicopathologic significance of PLIN1 in hepatocellular carcinoma (HCC), as well as its impact on the biological functions of HCC cells, and to investigate the underlying mechanisms involved. METHODS: Public high-throughput RNA microarray and RNA sequencing data were collected to examine PLIN1 levels and clinical significance in patients with HCC. Immunohistochemistry (IHC) and real-time quantitative reverse transcription polymerase chain reaction (RT‒qPCR) were conducted to assess the expression levels and the clinicopathological relevance of PLIN1 in HCC. Then, SK and Huh7 cells were transfected with a lentivirus overexpressing PLIN1. CCK8 assay, wound healing assay, transwell assay, and flow cytometric analysis were conducted to explore the effects of PLIN1 overexpression on HCC cell proliferation, migration, invasion, and cell cycle distribution. Ultimately, Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to investigate the underlying mechanisms of PLIN1 in HCC progression based on HCC differentially expressed genes and PLIN1 co-expressed genes. RESULTS: PLIN1 was markedly downregulated in HCC tissues, which correlated with a noticeably worse prognosis for HCC patients. Additionally, PLIN1 overexpression inhibited the proliferation, migration, and invasion of SK and Huh7 cells in vitro, as well as arresting the HCC cell cycle at the G0/G1 phase. More significantly, energy conversion-related biological processes, lipid metabolism, and cell cycle signalling pathways were the three most enriched molecular mechanisms. CONCLUSION: The present study revealed that PLIN1 downregulation is associated with poor prognosis in HCC patients and accelerated HCC progression by promoting cellular proliferation, migration, and metastasis, as well as the mechanisms underlying the regulation of lipid metabolism-related pathways in HCC.


Asunto(s)
Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Perilipina-1 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Biología Computacional/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Perilipina-1/metabolismo , Perilipina-1/genética , Pronóstico
7.
J Neural Transm (Vienna) ; 131(7): 739-753, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38630191

RESUMEN

Diagnosing and treating chronic orofacial pain is challenging due to its complex structure and limited understanding of its causes and mechanisms. In this study, we used RNA sequencing to identify differentially expressed genes (DEGs) in the rostral ventral medulla (RVM) and thalamus of rats with persistent orofacial pain, aiming to explore its development. DEGs were functionally analyzed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Results showed a significant association between immune response and pain in this model. Key DEG mRNA expression trends were further validated using real-time quantitative polymerase chain reaction (RT-PCR), confirming their crucial roles in chronic orofacial pain. After injecting complete Freund's adjuvant (CFA) into the bilateral temporomandibular joint cavity for 14 days, we observed 293 upregulated genes and 14 downregulated genes in the RVM, and 1086 upregulated genes and 37 downregulated genes in the thalamus. Furthermore, we identified 27 common DEGs with altered expression (upregulation) in both the thalamus and RVM, including Cd74, C3, Cxcl13, C1qb, Itgal, Fcgr2b, C5ar1, and Tlr2, which are pain-associated genes. Protein-protein interaction (PPI) analysis using Cytoscape revealed the involvement of Toll-like receptors, complement system, differentiation clusters, and antigen presentation-related proteins in the interaction between the thalamus and RVM. The results of this study show that the immune system seems to have a more significant influence on chronic orofacial pain. There may be direct or indirect influence between the thalamus and RVM, which may participate in the regulation of chronic orofacial pain.


Asunto(s)
Dolor Crónico , Dolor Facial , Bulbo Raquídeo , Ratas Sprague-Dawley , Tálamo , Animales , Dolor Facial/genética , Dolor Facial/metabolismo , Dolor Facial/fisiopatología , Bulbo Raquídeo/metabolismo , Masculino , Ratas , Dolor Crónico/genética , Dolor Crónico/metabolismo , Tálamo/metabolismo , Análisis de Secuencia de ARN , Modelos Animales de Enfermedad , Transcriptoma
8.
Chem Rec ; 24(7): e202300369, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38953343

RESUMEN

pH has been considered one of the paramount factors in bodily functions because most cellular tasks exclusively rely on precise pH values. In this context, the current techniques for pH sensing provide us with the futuristic insight to further design therapeutic and diagnostic tools. Thus, pH-sensing (electrochemically and optically) is rapidly evolving toward exciting new applications and expanding researchers' interests in many chemical contexts, especially in biomedical applications. The adaptation of cutting-edge technology is subsequently producing the modest form of these biosensors as wearable devices, which are providing us the opportunity to target the real-time collection of vital parameters, including pH for improved healthcare systems. The motif of this review is to provide insight into trending tech-based systems employed in real-time or in-vivo pH-responsive monitoring. Herein, we briefly go through the pH regulation in the human body to help the beginners and scientific community with quick background knowledge, recent advances in the field, and pH detection in real-time biological applications. In the end, we summarize our review by providing an outlook; challenges that need to be addressed, and prospective integration of various pH in vivo platforms with modern electronics that can open new avenues of cutting-edge techniques for disease diagnostics and prevention.


Asunto(s)
Técnicas Biosensibles , Concentración de Iones de Hidrógeno , Humanos , Dispositivos Electrónicos Vestibles , Técnicas Electroquímicas
9.
Inorg Chem ; 63(12): 5520-5529, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38488014

RESUMEN

The rational design of nonnoble-metal-based catalysts with high electroactivity and long-term stability, featuring controllable active sites, remains a significant challenge for achieving effective water electrolysis. Herein, a heterogeneous catalyst with a FeCo-S and Ni2P heterostructure (denoted FeCo-S/Ni2P/NF) grown on nickel foam (NF) was synthesized by a solvothermal method and low-temperature phosphorization. The FeCo-S/Ni2P/NF catalyst shows excellent electrocatalytic performance and stability in alkaline solution. The FeCo-S/Ni2P/NF catalyst demonstrates low overpotentials (η) for both the hydrogen evolution reaction (HER) (49 mV@10 mA cm-2) and the oxygen evolution reaction (OER) (279 mV@100 mA cm-2). Assembling the FeCo-S/Ni2P/NF catalyst as both cathode and anode in an electrolytic cell for overall water splitting (OWS) needs an ultralow cell voltage of 1.57 V to attain a current density (CD) of 300 mA cm-2. Furthermore, it demonstrates excellent durability, significantly outperforming the commercial Pt/C∥IrO2 system. The results of experiments indicate that the heterostructure and synergistic effect of FeCo-S and Ni2P can significantly enhance conductivity, facilitate mass/ion transport and gas evolution, and expose more active sites, thereby improving the catalytic activity of the electrocatalyst for the OWS. This study provides a rational approach for the development of commercially promising dual-functional electrocatalysts.

10.
Cell ; 138(3): 537-48, 2009 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-19665975

RESUMEN

Myosin VI is the only known molecular motor that moves toward the minus ends of actin filaments; thus, it plays unique roles in diverse cellular processes. The processive walking of myosin VI on actin filaments requires dimerization of the motor, but the protein can also function as a nonprocessive monomer. The molecular mechanism governing the monomer-dimer conversion is not clear. We report the high-resolution NMR structure of the cargo-free myosin VI cargo-binding domain (CBD) and show that it is a stable monomer in solution. The myosin VI CBD binds to a fragment of the clathrin-coated vesicle adaptor Dab2 with a high affinity, and the X-ray structure of the myosin VI CBD in complex with Dab2 reveals that the motor undergoes a cargo-binding-mediated dimerization. The cargo-binding-induced dimerization may represent a general paradigm for the regulation of processivity for myosin VI as well as other myosins, including myosin VII and myosin X.


Asunto(s)
Cadenas Pesadas de Miosina/química , Cadenas Pesadas de Miosina/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas Reguladoras de la Apoptosis , Vesículas Cubiertas por Clatrina/metabolismo , Cristalografía por Rayos X , Dimerización , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Alineación de Secuencia
11.
Perception ; : 3010066241270271, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129469

RESUMEN

Subsecond temporal processing is crucial for activities requiring precise timing. Here, we investigated perceptual learning of crossmodal (auditory-visual or visual-auditory) temporal interval discrimination (TID) and its impacts on unimodal (visual or auditory) TID performance. The research purpose was to test whether learning is based on a more abstract and conceptual representation of subsecond time, which would predict crossmodal to unimodal learning transfer. The experiments revealed that learning to discriminate a 200-ms crossmodal temporal interval, defined by a pair of visual and auditory stimuli, significantly reduced crossmodal TID thresholds. Moreover, the crossmodal TID training also minimized unimodal TID thresholds with a pair of visual or auditory stimuli at the same interval, even if crossmodal TID thresholds are multiple times higher than unimodal TID thresholds. Subsequent training on unimodal TID failed to reduce unimodal TID thresholds further. These results indicate that learning of high-threshold crossmodal TID tasks can benefit low-threshold unimodal temporal processing, which may be achieved through training-induced improvement of a conceptual representation of subsecond time in the brain.

12.
Altern Ther Health Med ; 30(10): 391-397, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38401070

RESUMEN

Background: Diabetes, a chronic disease metabolic disorder, commonly affects people. It is well-documented that aerobic exercise significantly reduces blood glucose in diabetic conditions. This study aimed to demonstrate the role of aerobic exercise on T2DM patients and cognitive impairment. Methods: We selected studies that published random controlled trials (RCTs) on the effects of aerobic exercise on cognitive function in patients with T2DM. However, the animal trials were we excluded in this study. We retrieved the data of random controlled trials from 8 databases based on the influences of aerobic exercise on cognitive function in patients with type 2 diabetes mellitus (T2DM). We utilized RevMan 5.3 software to analyze the data after evaluating the literature. Results: We selected 685 studies based on the information in the abstract and title after deleting the duplicate references. Then, we investigated the full text of 15. After full-text evaluation,we selected 10 random controlled trials to perform this comprehensive meta-analysis. We found that 10 studies derived the information of cognitive function between the test and the control groups and the cognitive function is significantly higher in the experimental group (SMD: 1.88; 95% Cl: 0.91,2.84; P < .01) than the control group. Moreover, the experimental group showed significantly higher minimum mental state examination (MMSE) (SMD: 2.06; 95% Cl: 0.96,3.14; P < .01) and Montreal Cognitive Assessment (MoCA) (SMD:1.62; 95% Cl: 0.54, 2.69; P < .01) than the normal group. Conclusion: Our findings demonstrated that aerobic exercise is crucially potent in T2DM patients and cognitive impairment, as evidenced by total cognitive function, MMSE, and MoCA. The above results should be warranted to verify with sophisticated clinical trials. In the future, aerobic exercise is suggested to guide patients'srecovery.


Asunto(s)
Cognición , Diabetes Mellitus Tipo 2 , Ejercicio Físico , Humanos , Cognición/fisiología , Disfunción Cognitiva/etiología , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/psicología , Ejercicio Físico/psicología , Terapia por Ejercicio/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Phytother Res ; 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180344

RESUMEN

Intracranial aneurysm (IA) is a common cerebrovascular disease. Immune system disorders and endothelial dysfunction are essential mechanisms of its pathogenesis. This study aims to explore the therapeutic effect and mechanism of Geniposide (Gen) on IA, which has a protective impact on endothelial cells and cardiovascular and cerebrovascular diseases. IA mouse models were administered intraperitoneal injections of geniposide for 2 weeks following elastase injection into the right basal ganglia of the brain for intervention. The efficacy of Gen in treating IA was evaluated through pathological testing and transcriptome sequencing analysis of Willis ring vascular tissue. The primary mechanism of action was linked to the expression of GSK3ß in Th17 cells. The percentage of splenic Th17 cell differentiation in IA mice was significantly inhibited by Gen. GSK3ß/STAT3, and other pathway protein expression levels were also significantly inhibited by Gen. Additionally, TNF-α and IL-23 cytokine contents were significantly downregulated after Gen treatment. These results indicated that Gen significantly inhibited the percentage of Th17 cell differentiation, an effect that was reversed upon overexpression of the GSK3B gene. Furthermore, Gen-treated, Th17 differentiation-inducing cell-conditioned medium significantly up-regulated the expression of tight junction proteins ZO-1, Occludin, and Claudin-5 in murine aortic endothelial cells. Administering the GSK3ß inhibitor Tideglusib to IA mice alleviated the severity of IA disease pathology and up-regulated aortic tight junction protein expression. In conclusion, Gen inhibits Th17 cell differentiation through GSK3ß, which reduces endothelial cell injury and up-regulates tight junction protein expression.

14.
J Craniofac Surg ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38534156

RESUMEN

Imparting procedural skills is challenging. Peyton's approach is an effective face-to-face teaching technique increasingly used in complex skills training. Institutions are beginning to incorporate online training as part of their procedural curriculum. We developed E-Peyton's to employ Peyton's approach through an electronic learning platform. The efficacy of E-Peyton's approach in teaching the interpretation of facial computed tomography (CT) scans is evaluated in this study. Naïve learners (n=41) were randomized into 2 groups based on teaching techniques employed: E-Peyton's (n=20) and Peyton's (n=21) approaches. The distance between the infraorbital margin and the posterior ledge was measured using a 3-part standardized measuring protocol on OsiriX. Twenty measurements were assessed for accuracy against the benchmark (±2 mm) at week 0 and week 1. Training durations were compared. Questionnaires were administered before and after the study to identify learners' acceptance of teaching techniques and their confidence in interpreting facial CT scans. Learners in both teaching techniques had comparable skills retention. Gap scores indicate significant improvement in learner's confidence levels regardless of teaching technique (P<0.05). Both teaching techniques were well-accepted by learners. E-Peyton's and Peyton's approaches required a similar training duration. The COVID-19 pandemic highlights the importance of effective remote learning platforms. E-Peyton's approach is comparable to that of Peyton's in all areas of assessment. E-Peyton's approach effectively automates Peyton's approach, allowing for standardized, high-quality procedural skills training while reducing manpower burden.

15.
Ergonomics ; : 1-17, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023126

RESUMEN

Car-lock sounds are designed to inform the lock status of vehicles. However, drivers often experience a lack of confidence regarding whether the car is locked, and car thefts persistently occur, frequently attributed to unlocked doors. Without identification of critical factors for evaluating effects of car-lock sounds on drivers, a strategy to car-lock sound design with increased locking efficiency remains implicit. This study proposes a method to identify critical factors influencing drivers' perceived certainty of car-lock status and behaviours during car-locking. An experiment was conducted to simulate the locking process and verbal protocol analysis was employed to comprehend participants' cognitive processes and behaviours. The results show that mechanical sound yielded high certainty and few hesitations, while tonal and crisp sound elicited low certainty and frequent hesitations. Seven critical factors on participants' behaviours and cognitive processes were identified, which provides a data-driven approach for future research in car-lock sounds evaluation and design.


The effect of car-lock sounds on drivers is significant to inform the locking status of vehicles. However, the strategy for car-lock sounds evaluation remains implicit. This study proposes a method to identify critical factors on drivers' behaviours and cognitive processes that would inform further car-lock sounds evaluation and design.

16.
J Perianesth Nurs ; 2024 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-39297820

RESUMEN

PURPOSE: To explore the analgesic characteristics of ultrasound-guided great auricular nerve (GAN) block to further improve pain management. DESIGN: Single-center, prospective, randomized, controlled, and double-blind preliminary clinical trial. METHODS: Thirty-seven patients who underwent middle ear surgery were included in this study: 15 in the GAN block group (the large ear nerve block [NB] group) and 22 in the traditional anesthesia group (control [CON] group). After induction of anesthesia, the NB group was given an ultrasound-guided GAN block (0.25 % Ropivacaine 2 mL), while the CON group was exempt from the GAN block. The patient's basic information, perioperative information, the region, and numeric rating scale of postoperative pain (at 1 hour, 6 hours, 12 hours, and 24 hours), and adverse reactions were recorded. Repeated measurement analysis, t test, and Fisher exact probability method were used for statistical analysis. FINDINGS: Compared with the CON group, the numeric rating scale in the NB group was lower after surgery (1 hour: 1.18 ± 0.35 vs 0.27 ± 0.20, P = .023; 6 hours: 1.82 ± 0.37 vs 1.13 ± 0.39, P = .203; 12 hours: 1.05 ± 0.19 vs 0.20 ± 0.10, P < .001; 24 hours: 0.55 ± 0.17 vs 0.13 ± 0.09, P = .029). In the NB group, the region of pain was merely concentrated in the ear canal. In the CON group, the pain extended to areas outside the ear canal, such as tragus and mastoid (at 12 hours, P = .006). There was no significant difference in the risk of postoperative adverse reactions between the two groups. CONCLUSIONS: Ultrasound-guided GAN block can relieve patients' pain after middle ear surgery, especially in the area outside the ear canal.

17.
Chembiochem ; 24(20): e202300330, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37671838

RESUMEN

[Fe]-hydrogenase catalyzes the heterolytic cleavage of H2 and reversible hydride transfer to methenyl-tetrahydromethanopterin. The iron-guanylylpyridinol (FeGP) cofactor is the prosthetic group of this enzyme, in which mononuclear Fe(II) is ligated with a pyridinol and two CO ligands. The pyridinol ligand fixes the iron by an acyl carbon and a pyridinol nitrogen. Biosynthetic proteins for this cofactor are encoded in the hmd co-occurring (hcg) genes. The function of HcgB, HcgC, HcgD, HcgE, and HcgF was studied by using structure-to-function analysis, which is based on the crystal structure of the proteins and subsequent enzyme assays. Recently, we reported the catalytic properties of HcgA and HcgG, novel radical S-adenosyl methionine enzymes, by using an in vitro biosynthesis assay. Here, we review the properties of [Fe]-hydrogenase and the FeGP cofactor, and the biosynthesis of the FeGP cofactor. Finally, we discuss the expected engineering of [Fe]-hydrogenase and the FeGP cofactor.


Asunto(s)
Hidrogenasas , Proteínas Hierro-Azufre , Hidrogenasas/metabolismo , Carbono/metabolismo , Proteínas Hierro-Azufre/química , Hierro/química
18.
Chembiochem ; 24(20): e202300390, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37455264

RESUMEN

Nicotinamide adenine dinucleotide (NADH) and nicotinamide adenine dinucleotide phosphate (NADPH) constitute major hydrogen donors for oxidative/reductive bio-transformations. NAD(P)H regeneration systems coupled with formate dehydrogenases (FDHs) represent a dreamful method. However, most of the native FDHs are NAD+ -dependent and suffer from insufficient reactivity compared to other enzymatic tools, such as glucose dehydrogenase. An efficient and competitive NADP+ -utilizing FDH necessitates the availability and robustness of NADPH regeneration systems. Herein, we report the engineering of a new FDH from Candida dubliniensis (CdFDH), which showed no strict NAD+ preference by a structure-guided rational/semi-rational design. A combinatorial mutant CdFDH-M4 (D197Q/Y198R/Q199N/A372S/K371T/▵Q375/K167R/H16L/K159R) exhibited 75-fold intensification of catalytic efficiency (kcat /Km ). Moreover, CdFDH-M4 has been successfully employed in diverse asymmetric oxidative/reductive processes with cofactor total turnover numbers (TTNs) ranging from 135 to 986, making it potentially useful for NADPH-required biocatalytic transformations.


Asunto(s)
Formiato Deshidrogenasas , NAD , NADP/metabolismo , NAD/metabolismo , Formiato Deshidrogenasas/genética , Formiato Deshidrogenasas/metabolismo , Ingeniería de Proteínas/métodos , Oxidación-Reducción
19.
Biomacromolecules ; 24(5): 2009-2021, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37104701

RESUMEN

Responsive drug release and low toxicity of drug carriers are important for designing controlled release systems. Here, a double functional diffractive o-nitrobenzyl, containing multiple electron-donating groups as a crosslinker and methacrylic acid (MAA) as a monomer, was used to decorate upconversion nanoparticles (UCNPs) to produce robust poly o-nitrobenzyl@UCNP nanocapsules using the distillation-precipitation polymerization and templating method. Poly o-nitrobenzyl@UCNP nanocapsules with a robust yolk-shell structure exhibited near-infrared (NIR) light-/pH-responsive properties. When the nanocapsules were exposed to 980 nm NIR irradiation, the loaded drug was efficiently released by altering the shell of the nanocapsules. The photodegradation kinetics of the poly o-nitrobenzyl@UCNP nanocapsules were studied. The anticancer drug, doxorubicin hydrochloride (DOX), was loaded at pH 8.0 with a loading efficiency of 13.2 wt %. The Baker-Lonsdale model was used to determine the diffusion coefficients under different release conditions to facilitate the design of dual-responsive drug release devices or systems. Additionally, cytotoxicity studies showed that the drug release of DOX could be efficiently triggered by NIR to kill cancer cells in a controlled manner.


Asunto(s)
Antineoplásicos , Nanocápsulas , Nanopartículas , Liberación de Fármacos , Antineoplásicos/química , Doxorrubicina/farmacología , Doxorrubicina/química , Nanopartículas/química , Polímeros/química , Concentración de Iones de Hidrógeno
20.
BMC Neurol ; 23(1): 139, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005567

RESUMEN

BACKGROUND: There are few reported studies on stigma in young and middle-aged stroke patients during the rehabilitation period, however, the rehabilitation period plays a key role in the patients' disease regression. Exploring the level of stigma and the influencing factors in young and middle-aged stroke patients during the rehabilitation period is crucial for determining how to reduce the level of stigma and improve the patients' motivation for rehabilitation treatment. Therefore, this study investigated the level of stigma in young and middle-aged stroke patients and analyzed the factors influencing stigma in order to provide a reference or basis for healthcare professionals to develop effective and targeted stigma intervention programs. METHODS: Using a convenience sampling method, 285 young and middle-aged stroke patients admitted to the rehabilitation medicine department of a tertiary care hospital in Shenzhen, China, from November 2021 to September 2022 were selected and surveyed using a general information questionnaire, the Stroke Stigma Scale(SSS), the Barthel Index(BI), and the Positive and Negative Emotions Scale(PANAS), and multiple linear regression and smoothed curve fitting were used to analyze the factors influencing the stigma of young and middle-aged stroke patients during the rehabilitation period. RESULTS: SSS score of 45.08 ± 11.06, univariate analysis of age, occupation, education level, pre-stroke monthly income, insurance type, comorbid chronic disease status, primary caregiver, BI, positive and negative emotion as factors influencing stigma. Multiple linear regression showed that age, pre-stroke monthly income, BI, positive and negative emotions were independent influences on stigma in young and middle-aged stroke patients, explaining 58.0% of the total variance in stigma. A smoothed curve fit revealed a curvilinear relationship between the above influences and stigma. CONCLUSION: Young and middle-aged stroke patients have a moderate level of stigma. Medical staff should focus on young patients aged 18-44 years, those with high monthly income before the stroke, those with poor self-care ability, and those with low positive and high negative emotion scores, and conduct early assessments and adopt targeted intervention programs according to the influencing factors to reduce the stigma of young and middle-aged stroke patients, improve their motivation for rehabilitation, and help them return to their families and society as soon as possible. TRIAL REGISTRATION: Registration number of China Clinical Trials Registration Center: 20,220,328,004-FS01.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Estudios Transversales , Pacientes , Estigma Social , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/psicología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA