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1.
Nature ; 614(7946): 81-87, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725999

RESUMEN

Micro-LEDs (µLEDs) have been explored for augmented and virtual reality display applications that require extremely high pixels per inch and luminance1,2. However, conventional manufacturing processes based on the lateral assembly of red, green and blue (RGB) µLEDs have limitations in enhancing pixel density3-6. Recent demonstrations of vertical µLED displays have attempted to address this issue by stacking freestanding RGB LED membranes and fabricating top-down7-14, but minimization of the lateral dimensions of stacked µLEDs has been difficult. Here we report full-colour, vertically stacked µLEDs that achieve, to our knowledge, the highest array density (5,100 pixels per inch) and the smallest size (4 µm) reported to date. This is enabled by a two-dimensional materials-based layer transfer technique15-18 that allows the growth of RGB LEDs of near-submicron thickness on two-dimensional material-coated substrates via remote or van der Waals epitaxy, mechanical release and stacking of LEDs, followed by top-down fabrication. The smallest-ever stack height of around 9 µm is the key enabler for record high µLED array density. We also demonstrate vertical integration of blue µLEDs with silicon membrane transistors for active matrix operation. These results establish routes to creating full-colour µLED displays for augmented and virtual reality, while also offering a generalizable platform for broader classes of three-dimensional integrated devices.

2.
Proc Natl Acad Sci U S A ; 121(22): e2404007121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38768347

RESUMEN

Sensations of heat and touch produced by receptors in the skin are of essential importance for perceptions of the physical environment, with a particularly powerful role in interpersonal interactions. Advances in technologies for replicating these sensations in a programmable manner have the potential not only to enhance virtual/augmented reality environments but they also hold promise in medical applications for individuals with amputations or impaired sensory function. Engineering challenges are in achieving interfaces with precise spatial resolution, power-efficient operation, wide dynamic range, and fast temporal responses in both thermal and in physical modulation, with forms that can extend over large regions of the body. This paper introduces a wireless, skin-compatible interface for thermo-haptic modulation designed to address some of these challenges, with the ability to deliver programmable patterns of enhanced vibrational displacement and high-speed thermal stimulation. Experimental and computational investigations quantify the thermal and mechanical efficiency of a vertically stacked design layout in the thermo-haptic stimulators that also supports real-time, closed-loop control mechanisms. The platform is effective in conveying thermal and physical information through the skin, as demonstrated in the control of robotic prosthetics and in interactions with pressure/temperature-sensitive touch displays.


Asunto(s)
Tacto , Realidad Virtual , Tecnología Inalámbrica , Humanos , Tecnología Inalámbrica/instrumentación , Tacto/fisiología , Piel , Robótica/instrumentación , Robótica/métodos
3.
Proc Natl Acad Sci U S A ; 120(6): e2217828120, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36716364

RESUMEN

Thermal sensations contribute to our ability to perceive and explore the physical world. Reproducing these sensations in a spatiotemporally programmable manner through wireless computer control could enhance virtual experiences beyond those supported by video, audio and, increasingly, haptic inputs. Flexible, lightweight and thin devices that deliver patterns of thermal stimulation across large areas of the skin at any location of the body are of great interest in this context. Applications range from those in gaming and remote socioemotional communications, to medical therapies and physical rehabilitation. Here, we present a set of ideas that form the foundations of a skin-integrated technology for power-efficient generation of thermal sensations across the skin, with real-time, closed-loop control. The systems exploit passive cooling mechanisms, actively switchable thermal barrier interfaces, thin resistive heaters and flexible electronics configured in a pixelated layout with wireless interfaces to portable devices, the internet and cloud data infrastructure. Systematic experimental studies and simulation results explore the essential mechanisms and guide the selection of optimized choices in design. Demonstration examples with human subjects feature active thermoregulation, virtual social interactions, and sensory expansion.


Asunto(s)
Piel , Realidad Virtual , Humanos , Electrónica , Sensación Térmica , Comunicación
4.
Am J Transplant ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39155023

RESUMEN

We evaluated the liver transplantation (LT) criteria in acute-on-chronic liver failure (ACLF), incorporating an urgent living-donor LT (LDLT) program. Critically ill patients with a Chronic Liver Failure Consortium (CLIF-C) ACLF score (CLIF-C_ACLF_score) ≥65, previously considered unsuitable for LT, were included to explore the excess mortality threshold of the CLIF-C_ACLF_score (CLIF-C_ACLF_score_threshold). We followed 854 consecutive patients with ACLF (276 ACLF grade 2 and 215 ACLF grade 3) over 10 years among 4432 LT recipients between 2008 and 2019. For advanced ACLF patients without immediate deceased-donor (DD) allocation, an urgent LDLT program was expedited. The CLIF-C_ACLF_score_threshold was determined by the metrics of transplant survival benefit: >60% 1-year and >50% 5-year survival rate. In predicting post-LT mortality, the CLIF-C_ACLF_score outperformed the (model for end-stage liver disease-sodium) MELD-Na and (model for end-stage liver disease) MELD-3.0 scores but was comparable to the Sundaram ACLF-LT-mortality score. A CLIF-C_ACLF_score ≥65 (n = 54) demonstrated posttransplant survival benefits, with 1-year and 5-year survival rates of 66.7% and 50.4% (P < .001), respectively. Novel CLIF-C_ACLF_score_threshold for 1-year and 5-year mortalities was 70 and 69, respectively. A CLIF-C_ACLF_score-based nomogram for predicting survival probabilities, integrating cardiovascular disease, diabetes, and donor type (LDLT vs DDLT), was generated. This study suggests reconsidering the criteria for unsuitable LT with a CLIF-C_ACLF_score ≥65. Implementing a timely salvage LT strategy, and incorporating urgent LDLT, can enhance survival rates.

5.
Environ Res ; 249: 118437, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38346486

RESUMEN

The widespread prevalence of micro and nanoplastics in the environment raises concerns about their potential impact on human health. Recent evidence demonstrates the presence of nanoplastics in human blood and tissues following ingestion and inhalation, yet the specific risks and mechanisms of nanoplastic toxicity remain inadequately understood. In this study, we aimed to explore the molecular mechanisms underlying the toxicity of nanoplastics at both systemic and molecular levels by analyzing the transcriptomic/metabolomic responses and signaling pathways in the intestines of mice after oral administration of nanoplastics. Transcriptome analysis in nanoplastic-administered mice revealed a notable upregulation of genes involved in pro-inflammatory immune responses. In addition, nanoplastics substantially reduced the expression of tight junction proteins, including occludin, zonula occluden-1, and tricellulin, which are crucial for maintaining gut barrier integrity and function. Importantly, nanoplastic administration increased gut permeability and exacerbated dextran sulfate sodium-induced colitis. Further investigation into the underlying molecular mechanisms highlighted significant activation of signaling transsducer and activator of transcription (STAT)1 and STAT6 by nanoplastic administration, which was in line with the elevation of interferon and JAK-STAT pathway signatures identified through transcriptome enrichment analysis. Additionally, the consumption of nanoplastics specifically induced nuclear factor kappa-B (NF-κB) and extracellular signal-regulated kinase (ERK)1/2 signaling pathways in the intestines. Collectively, this study identifies molecular mechanisms contributing to adverse effects mediated by nanoplastics in the intestine, providing novel insights into the pathophysiological consequences of nanoplastic exposure.


Asunto(s)
Factor de Transcripción STAT1 , Animales , Ratones , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT1/genética , Transcriptoma/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Factor de Transcripción STAT6/metabolismo , Factor de Transcripción STAT6/genética , Ratones Endogámicos C57BL , Nanopartículas/toxicidad , Metabolómica , Masculino , Colitis/inducido químicamente , Colitis/metabolismo
6.
Prehosp Emerg Care ; : 1-8, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38787646

RESUMEN

OBJECTIVE: Recent studies have shown inconsistent results regarding the association between QRS characteristics and survival outcomes in patients with cardiac arrest and pulseless electrical activity (PEA) rhythms. This meta-analysis aimed to identify the usefulness of QRS width and frequency as prognostic tools for outcomes in patients with cardiac arrest and PEA rhythm. METHODS: Extensive searches were conducted using Medline, Embase, and the Cochrane Library to find articles published from database inception to 4 June 2023. Studies that assessed the association between the QRS characteristics of cardiac arrest patients with PEA rhythm and survival outcomes were included. The Newcastle-Ottawa Scale was used to assess the methodological quality of the included studies. RESULTS: A total of 9727 patients from seven observational studies were included in this systematic review and meta-analysis. The wide QRS group (QRS ≥ 120 ms) was associated with significantly higher odds of mortality than the narrow QRS group (QRS < 120 ms) (odds ratio (OR) = 1.86, 95% confidence interval (CI) = 1.11-3.11, I2 = 58%). The pooled OR for mortality was significantly higher in patients with a QRS frequency of < 60/min than in those with a QRS frequency of ≥ 60/min (OR = 1.90, 95% CI = 1.19-3.02, I2 = 65%). CONCLUSIONS: Wide QRS width or low QRS frequency is associated with increased odds of mortality in patients with PEA cardiac arrest. These findings may be beneficial to guide the disposition of cardiac arrest patients with PEA during resuscitation.

7.
Ann Hepatol ; 29(4): 101474, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38331385

RESUMEN

INTRODUCTION AND OBJECTIVES: Acute kidney injury (AKI) is prevalent and has deleterious effects on postoperative outcomes following liver transplantation (LT). The impact of nonselective beta-blockers (NSBBs) in patients with liver cirrhosis remains controversial. This study investigated the association between preoperative NSBB use and AKI after living donor LT (LDLT). PATIENTS AND METHODS: We evaluated 2,972 adult LDLT recipients between January 2012 and July 2022. The patients were divided into two groups based on the preoperative NSBB use. Propensity score matched (PSM) and inverse probability of treatment weighting (IPTW) analyses were performed to evaluate the association between preoperative NSBB use and postoperative AKI. Multiple logistic regression analyses were also used to identify the risk factors for AKI. RESULTS: The overall incidence of AKI was 1,721 (57.9%) cases. The NSBB group showed a higher incidence of AKI than the non-NSBB group (62.4% vs. 56.7%; P = 0.011). After PSM and IPTW analyses, no significant difference in the incidence of AKI was found between the two groups (Odds ratio, OR 1.13, 95% confidence interval, CI 0.93-1.37, P = 0.230, PSM analysis; OR 1.20, 95% CI 0.99-1.44, P = 0.059, IPTW analysis). In addition, preoperative NSBB use was not associated with AKI after multivariate logistic regression analysis (OR 1.16, 95% CI 0.96-1.40, P = 0.118). CONCLUSIONS: Preoperative NSBB use was not associated with AKI after LDLT. Further studies are needed to validate our results.


Asunto(s)
Lesión Renal Aguda , Antagonistas Adrenérgicos beta , Trasplante de Hígado , Donadores Vivos , Puntaje de Propensión , Humanos , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Trasplante de Hígado/efectos adversos , Femenino , Masculino , Persona de Mediana Edad , Incidencia , Factores de Riesgo , Antagonistas Adrenérgicos beta/uso terapéutico , Antagonistas Adrenérgicos beta/efectos adversos , Estudios Retrospectivos , Adulto , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Cuidados Preoperatorios/métodos , Cirrosis Hepática/cirugía , Cirrosis Hepática/complicaciones , Medición de Riesgo
8.
Int Endod J ; 57(6): 759-768, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38436525

RESUMEN

AIM: Among numerous constituents of Panax ginseng, a constituent named Ginsenoside Rb1 (G-Rb1) has been studied to diminish inflammation associated with diseases. This study investigated the anti-inflammatory properties of G-Rb1 on human dental pulp cells (hDPCs) exposed to lipopolysaccharide (LPS) and aimed to determine the underlying molecular mechanisms. METHODOLOGY: The KEGG pathway analysis was performed after RNA sequencing in G-Rb1- and LPS-treated hDPCs. Reverse-transcription polymerase chain reaction (RT-PCR) and western blot analysis were used for the assessment of cell adhesion molecules and inflammatory cytokines. Statistical analysis was performed with one-way ANOVA and the Student-Newman-Keuls test. RESULTS: G-Rb1 did not exhibit any cytotoxicity within the range of concentrations tested. However, it affected the levels of TNF-α, IL-6 and IL-8, as these showed reduced levels with exposure to LPS. Additionally, less mRNA and protein expressions of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were shown. With the presence of G-Rb1, decreased levels of PI3K/Akt, phosphorylated IκBα and p65 were also observed. Furthermore, phosphorylated ERK and JNK by LPS were diminished within 15, 30 and 60 min of G-Rb1 exposure; however, the expression of non-phosphorylated ERK and JNK remained unchanged. CONCLUSIONS: G-Rb1 suppressed the LPS-induced increase of cell adhesion molecules and inflammatory cytokines, while also inhibiting PI3K/Akt, phosphorylation of NF-κB transcription factors, ERK and JNK of MAPK signalling in hDPCs.


Asunto(s)
Pulpa Dental , Ginsenósidos , Lipopolisacáridos , FN-kappa B , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Ginsenósidos/farmacología , Humanos , Pulpa Dental/efectos de los fármacos , Pulpa Dental/citología , Pulpa Dental/metabolismo , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , FN-kappa B/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Inflamación/metabolismo , Células Cultivadas , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Citocinas/metabolismo , Western Blotting
9.
Artículo en Inglés | MEDLINE | ID: mdl-39275965

RESUMEN

Monzogranite is known for its high surface area and cation exchange capacity, which play a crucial role in ameliorating the challenges by enhancing nutrient adsorption and facilitating nutrient availability during the weaning period. Weaned crossbred piglets (Duroc × Yorkshire × Landrace), initially weighing 5.36 ± 0.26 kg, were allocated into four treatments with 6 replicates each (10 pigs per replicate). The treatments encompassed CON (basal diet), Z0.1 (0.1% monzogranite supplementation in basal diet), Z0.2 (0.2% monzogranite supplementation), and Z0.3 (0.3% monzogranite supplementation). In phase 1, a linear increase in total average daily gain (ADG) was observed across treatment groups, with a concomitant linear increase in ADG and gain-to-feed ratio (G/F). The overall results showed a linear increase in ADG and G/F. A linear decrease in aspartate aminotransferase and lactate dehydrogenase levels was observed across treatment groups. Conversely, no significant differences were noted in the levels of albumin, alkaline phosphatase, alanine aminotransferase, high-density lipoprotein, low-density lipoprotein, total cholesterol, blood urea nitrogen, triglycerides, and gamma-glutamyl transferase among the treatment groups. Faecal scoring indicated a linear reduction in scores at Day 7 among the treatment groups. However, no significant differences were observed at Days 14 and 28. The assessment of immunoglobulins demonstrated a significant increase in both immunoglobulin G and immunoglobulin A levels in the Z0.1 treatment group compared to the CON. In both phase 1 and phase 2, a linear decrease in cortisol levels was evident. In conclusion, a linear increase in total ADG and G/F during phase 1, sustained across both phases, suggests monzogranite potential to enhance growth performance. Moreover, stress mitigation was shown through a consistent linear decrease in cortisol levels across phases. These findings underscore monzogranite multifaceted impact, emphasizing its potential as a dietary supplement to enhance growth, liver health, and stress resilience in weanling pigs.

10.
Environ Geochem Health ; 46(7): 240, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849660

RESUMEN

The present study firstly reports surface sediment from the subsea depth of 200 m as a potential natural peloid. The fine-silt sediment exhibited a consistent clay mineral composition dominated by illite, chlorite, kaolinite, and diatomite. The most abundant clay mineral was illite/mica, with other minerals loosely packed in a face-to-face orientation. The thermal conductivity, specific heat capacity, and cation-exchange capacity of the sediment were in the range 0.855-0.885 W/m K, 2.718-2.821 J/g °C, and 23.06-32.96 cmol/kg, respectively. The concentrations of most toxic elements in the sediment were considerably lower than the limits set by domestic cosmetic regulations and other international standards. The analyzed samples exhibited similar properties to those of previously reported peloids, thus making them suitable for use in the field of pelotherapy; furthermore, the consistency in data across a wide peloid-distribution area is expected to enable economically viable mining. Future investigations should aim to to evaluate the long-term effects on the skin, the bioavailability of potentially hazardous substances, and the therapeutic efficacy for various skin conditions.


Asunto(s)
Arcilla , Sedimentos Geológicos , Peloterapia , Sedimentos Geológicos/química , República de Corea , Arcilla/química , Silicatos de Aluminio/química , Minerales/química , Minerales/análisis , Monitoreo del Ambiente/métodos
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