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1.
Nat Commun ; 15(1): 5376, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918409

RESUMEN

Kagome lattice has been actively studied for the possible realization of frustration-induced two-dimensional flat bands and a number of correlation-induced phases. Currently, the search for kagome systems with a nearly dispersionless flat band close to the Fermi level is ongoing. Here, by combining theoretical and experimental tools, we present Sc3Mn3Al7Si5 as a novel realization of correlation-induced almost-flat bands in the kagome lattice in the vicinity of the Fermi level. Our magnetic susceptibility, 27Al nuclear magnetic resonance, transport, and optical conductivity measurements provide signatures of a correlated metallic phase with tantalizing ferromagnetic instability. Our dynamical mean-field calculations suggest that such ferromagnetic instability observed originates from the formation of nearly flat dispersions close to the Fermi level, where electron correlations induce strong orbital-selective renormalization and manifestation of the kagome-frustrated bands. In addition, a significant negative magnetoresistance signal is observed, which can be attributed to the suppression of flat-band-induced ferromagnetic fluctuation, which further supports the formation of flat bands in this compound. These findings broaden a new prospect to harness correlated topological phases via multiorbital correlations in 3d-based kagome systems.

2.
Int J Mol Sci ; 25(8)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38673901

RESUMEN

Irreversible electroporation (IRE) is a prominent non-thermal ablation method widely employed in clinical settings for the focal ablation therapy of solid tumors. Utilizing high-voltage, short-duration electric pulses, IRE induces perforation defects in the cell membrane, leading to apoptotic cell death. Despite the promise of irreversible electroporation (IRE) in clinical applications, it faces challenges concerning the coverage of target tissues for ablation, particularly when compared to other thermal ablation therapies such as radiofrequency ablation, microwave ablation, and cryoablation. This study aims to investigate the induced hyperthermal effect of IRE by applying a polydopamine nanoparticle (Dopa NP) coating on the electrode. We hypothesize that the induced hyperthermal effect enhances the therapeutic efficacy of IRE for cancer ablation. First, we observed the hyperthermal effect of IRE using Dopa NP-coated electrodes in hydrogel phantom models and then moved to in vivo models. In particular, in in vivo animal studies, the IRE treatment of rabbit hepatic lobes with Dopa NP-coated electrodes exhibited a two-fold higher increase in temperature (ΔT) compared to non-coated electrodes. Through a comprehensive analysis, we found that IRE treatment with Dopa NP-coated electrodes displayed the typical histological signatures of hyperthermal ablation, including the disruption of the hepatic cord and lobular structure, as well as the infiltration of erythrocytes. These findings unequivocally highlight the combined efficacy of IRE with Dopa NPs for electroporation and the hyperthermal ablation of target cancer tissues.


Asunto(s)
Electrodos , Electroporación , Indoles , Nanopartículas , Polímeros , Indoles/química , Indoles/farmacología , Animales , Polímeros/química , Nanopartículas/química , Electroporación/métodos , Conejos , Hígado/cirugía , Hígado/efectos de los fármacos , Hipertermia Inducida/métodos
3.
Materials (Basel) ; 16(23)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38068019

RESUMEN

Wire bonding, one of the methods for electrically connecting a semiconductor chip with a substrate, involves attaching thin metal wires to pads. It is the oldest electrical connection method that exhibits high compatibility with other processes. The metal wires used for electrical connection in wire bonding are mainly made of Au, Cu, and Ag. After the wire bonding, molding is performed using the epoxy molding compound (EMC). However, EMC inevitably contains ions such as halogen elements. In addition, it absorbs moisture due to its hydrophilicity, creating a corrosive environment with electrolytes. In this study, we evaluated the influence of hydrochloric acid concentration on corrosion behavior between Au or Cu bonding wires and sputtered Al bond pads. The electrochemical factors such as corrosion potential difference (ΔE), galvanic corrosion current density (ig), and anodic and cathodic Tafel slopes were found to influence galvanic corrosion behavior. Galvanic corrosion tendency in first bond and second bond areas of PCB unit specimen was confirmed.

4.
Technol Cancer Res Treat ; 22: 15330338221147122, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37861099

RESUMEN

Irreversible electroporation (IRE) is a non-thermal and minimal invasive modality to ablate pathologic lesions such as hepatic tumors. Histological analysis of the initial lesions after IRE can help predict ablation efficacy. We aimed to investigate the histological characteristics of early hepatic lesions after IRE application using animal models. IRE (1500 V/cm, a pulse length of 100 µs, 60 or 90 pulses) was applied to the liver of miniature pigs. H&E and TUNEL staining were performed and analyzed. Ablated zones of pig liver were discolored and separated from the normal zone after IRE. Histologic characteristics of ablation zones included preserved hepatic lobular architecture with a unique hexagonal-like structure. Apoptotic cells were detected, and sinusoidal dilatation and blood congestion were observed, but hepatic arteries and bile ducts were intact around the ablation zones. The early lesions obtained by delivering monophasic square wave pulses through needle electrodes reflected typical histological changes induced by IRE. Therefore, it was found that the histological assessment of the early hepatic lesion after IRE can be utilized to predict the IRE ablation effect.


Asunto(s)
Técnicas de Ablación , Neoplasias , Porcinos , Animales , Modelos Animales , Hígado/cirugía , Coloración y Etiquetado , Electroporación
5.
Dose Response ; 18(3): 1559325820946923, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848526

RESUMEN

The effect of remote ischemic preconditioning (RIPC) has been proposed that mediates the protective response in ischemia reperfusion injury (IRI) of various organs. In this study, we investigated the effect of RIPC in hepatic IRI, by assessing biomarker of oxidative stress and inflammatory cytokines. Moreover, we intended to demonstrate any such protective effect through nitric oxide (NO). Twenty-five rats were divided into the 5 groups: (1) Sham; (2) RIPC; (3) hepatic IRI; (4) RIPC + hepatic IRI; (5) C-PTIO, 2-(4-carboxyphenyl)-4,5dihydro-4,4,5,5-tetramethyl-1H-imidazolyl-1-oxy-3oxide, + RIPC + hepatic IRI. RIPC downregulated the level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), histologic damage, and activity of Malondialdehyde (MDA). However, there was no significant reduction in the level of tumor necrosis factor-alpha (TNF-α) and nuclear factor kappa B (NF-κB). AST and ALT levels, and hepatic tissue morphology in the C-PTIO group showed a significant improvement compared to those of the RIPC + hepatic IRI group. The application of RIPC before hepatic ischemia downregulated the oxidative stress, not the inflammatory cytokines. Moreover, these protective effect of RIPC would be mediated through the activation of NO as well as anti-oxidant effect.

6.
Medicine (Baltimore) ; 99(34): e21847, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32846834

RESUMEN

RATIONALE: Lesch-Nyhan syndrome (LNS) is an X-linked recessive disorder presenting with uric acid overproduction, neurocognitive disability, and behavioral disturbances. Inhalational anesthesia has been frequently used in LNS patients undergoing surgery. Characteristic compulsive self-injurious behavior and high risk of emesis may hinder inhalational induction. Propofol may be beneficial for these patients because of its easy and rapid titration for anesthetic depth during induction, early recovery from anesthesia, and antiemetic effect as well as uricosuric effect. PATIENT CONCERNS: A 16-year-old male adolescent was scheduled for percutaneous nephrolithotomy. He exhibited poorly controlled muscle, self-injurious behaviors and intellectual disability. DIAGNOSIS: The patient presented with neurodevelopmental delay in the first year of life, and was diagnosed with LNS, with a substitution of phenylalanine to leucine in hypoxanthine-guanine phosphoribosyltransferase (HPRT) 1 gene on the X-chromosome at 3 years of age. INTERVENTIONS: Total intravenous anesthesia was used for induction and maintenance of anesthesia with propofol and remifentanil using target-controlled infusion. OUTCOMES: Time to recovery of consciousness was prolonged after uneventful surgery. Serum uric acid levels gradually increased during postoperative period. LESSONS: Propofol anesthesia using target-controlled infusion does not provide significant clinical advantages in rapid emergence from anesthesia and management of hyperuricemia in LNS patients undergoing urological surgery.


Asunto(s)
Anestesia General/efectos adversos , Hipoxantina Fosforribosiltransferasa/genética , Síndrome de Lesch-Nyhan/psicología , Propofol/administración & dosificación , Administración Intravenosa , Adolescente , Periodo de Recuperación de la Anestesia , Anestesia General/métodos , Humanos , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/etiología , Discapacidad Intelectual/etiología , Cálculos Renales/cirugía , Síndrome de Lesch-Nyhan/sangre , Síndrome de Lesch-Nyhan/diagnóstico , Síndrome de Lesch-Nyhan/genética , Masculino , Nefrolitotomía Percutánea/métodos , Trastornos del Neurodesarrollo/etiología , Conducta Autodestructiva/etiología , Resultado del Tratamiento , Ácido Úrico/sangre , Vómitos/inducido químicamente
7.
Medicine (Baltimore) ; 99(29): e21060, 2020 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-32702848

RESUMEN

BACKGROUND: Postoperative sore throat (POST) is an important concern in surgical patients undergoing endotracheal intubation. Its prevalence after thyroidectomy is up to 80%. The current study aimed to assess the effect of dexmedetomidine and remifentanil on postoperative sore throat. METHODS: Seventy-four patients who underwent thyroidectomy were randomized to receive either dexmedetomidine (group D) or remifentanil (group R). At anesthesia induction, group D received dexmedetomidine 1 µg/kg over 10 minutes, followed by continuous dexmedetomidine infusion at 0.3 to 0.6 µg/kg/hour during surgery. Group R received remifentanil of 3 to 4 ng/ml during induction, followed by 1.5 to 2.5 ng/ml remifentanil infusion during surgery. POST at rest and swallowing was assessed during the first 24 hours in serial time periods (0-1, 1-6, and 6-24 hours). Hoarseness and postoperative pain score were also assessed. RESULTS: POST incidence at rest (0-1, 1-6, and 6-24 hours) and swallowing (1-6 and 6-24 hours) was lower in group D than in group R. POST severity was significantly lower in group D than in group R during each time period. The incidence of postoperative hoarseness was also lower in group D than in group R at 1 to 6 and 6 to 24 hours. The postoperative pain score was lower in group D than in group R during each time period. CONCLUSION: Intraoperative dexmedetomidine infusion reduced the incidence and severity of POST for 24 hours after thyroidectomy.


Asunto(s)
Dexmedetomidina/uso terapéutico , Faringitis/tratamiento farmacológico , Faringitis/etiología , Periodo Posoperatorio , Remifentanilo/uso terapéutico , Tiroidectomía/efectos adversos , Adulto , Analgésicos no Narcóticos/normas , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/normas , Analgésicos Opioides/uso terapéutico , Dexmedetomidina/normas , Femenino , Humanos , Intubación Intratraqueal/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/tratamiento farmacológico , Remifentanilo/normas , Tiroidectomía/métodos
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