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1.
Nature ; 603(7902): 631-636, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35322249

RESUMEN

Metastable phases-kinetically favoured structures-are ubiquitous in nature1,2. Rather than forming thermodynamically stable ground-state structures, crystals grown from high-energy precursors often initially adopt metastable structures depending on the initial conditions, such as temperature, pressure or crystal size1,3,4. As the crystals grow further, they typically undergo a series of transformations from metastable phases to lower-energy and ultimately energetically stable phases1,3,4. Metastable phases sometimes exhibit superior physicochemical properties and, hence, the discovery and synthesis of new metastable phases are promising avenues for innovations in materials science1,5. However, the search for metastable materials has mainly been heuristic, performed on the basis of experiences, intuition or even speculative predictions, namely 'rules of thumb'. This limitation necessitates the advent of a new paradigm to discover new metastable phases based on rational design. Such a design rule is embodied in the discovery of a metastable hexagonal close-packed (hcp) palladium hydride (PdHx) synthesized in a liquid cell transmission electron microscope. The metastable hcp structure is stabilized through a unique interplay between the precursor concentrations in the solution: a sufficient supply of hydrogen (H) favours the hcp structure on the subnanometre scale, and an insufficient supply of Pd inhibits further growth and subsequent transition towards the thermodynamically stable face-centred cubic structure. These findings provide thermodynamic insights into metastability engineering strategies that can be deployed to discover new metastable phases.

2.
Small ; 20(23): e2308815, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38161254

RESUMEN

Non-neural extracellular matrix (ECM) has limited application in humanized physiological neural modeling due to insufficient brain-specificity and safety concerns. Although brain-derived ECM contains enriched neural components, certain essential components are partially lost during the decellularization process, necessitating augmentation. Here, it is demonstrated that the laminin-augmented porcine brain-decellularized ECM (P-BdECM) is xenogeneic factor-depleted as well as favorable for the regulation of human neurons, astrocytes, and microglia. P-BdECM composition is comparable to human BdECM regarding brain-specificity through the matrisome and gene ontology-biological process analysis. As augmenting strategy, laminin 111 supplement promotes neural function by synergic effect with laminin 521 in P-BdECM. Annexin A1(ANXA1) and Peroxiredoxin(PRDX) in P-BdECM stabilized microglial and astrocytic behavior under normal while promoting active neuroinflammation in response to neuropathological factors. Further, supplementation of the brain-specific molecule to non-neural matrix also ameliorated glial cell inflammation as in P-BdECM. In conclusion, P-BdECM-augmentation strategy can be used to recapitulate humanized pathophysiological cerebral environments for neurological study.


Asunto(s)
Encéfalo , Diferenciación Celular , Matriz Extracelular , Laminina , Humanos , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Laminina/química , Encéfalo/metabolismo , Animales , Neuronas/metabolismo , Enfermedades Neuroinflamatorias/metabolismo , Porcinos , Astrocitos/metabolismo , Microglía/metabolismo , Inflamación/patología
3.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34475212

RESUMEN

Toll-like receptor 4 (Tlr) interactor with leucine-rich repeats (Tril) functions as a Tlr coreceptor to mediate innate immunity in adults. In Xenopus embryos, Tril triggers degradation of the transforming growth factor ß (Tgf-ß) family inhibitor, Smad7. This enhances bone morphogenetic protein (Bmp) signaling to enable ventral mesoderm to commit to a blood fate. Here, we show that Tril simultaneously dampens Nodal signaling by catalytically activating the ubiquitin ligase NEDD4 Like (Nedd4l). Nedd4l then targets Nodal receptors for degradation. How Tril signals are transduced in a nonimmune context is unknown. We identify the ubiquitin ligase Pellino2 as a protein that binds to the cytoplasmic tail of Tril and subsequently forms a complex with Nedd4l and another E3 ligase, TNF-receptor associated factor 6 (Traf6). Pellino2 and Traf6 are essential for catalytic activation of Nedd4l, both in Xenopus and in mammalian cells. Traf6 ubiquitinates Nedd4l, which is then recruited to membrane compartments where activation occurs. Collectively, our findings reveal that Tril initiates a noncanonical Tlr-like signaling cascade to activate Nedd4l, thereby coordinately regulating the Bmp and Nodal arms of the Tgf-ß superfamily during vertebrate development.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/fisiología , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Proteína Nodal/metabolismo , Proteínas Nucleares/metabolismo , Transducción de Señal/fisiología , Animales , Desarrollo Embrionario , Células HEK293 , Células HeLa , Humanos , Ubiquitina-Proteína Ligasas Nedd4/genética , Fosforilación , Xenopus
4.
Proc Natl Acad Sci U S A ; 118(16)2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33853949

RESUMEN

Fibroblast growth factor 23 (FGF23), a hormone generally derived from bone, is important in phosphate and vitamin D homeostasis. In acute kidney injury (AKI) patients, high-circulating FGF23 levels are associated with disease progression and mortality. However, the organ and cell type of FGF23 production in AKI and the molecular mechanism of its excessive production are still unidentified. For insight, we investigated folic acid (FA)-induced AKI in mice. Interestingly, simultaneous with FGF23, orphan nuclear receptor ERR-γ expression is increased in the liver of FA-treated mice, and ectopic overexpression of ERR-γ was sufficient to induce hepatic FGF23 production. In patients and in mice, AKI is accompanied by up-regulated systemic IL-6, which was previously identified as an upstream regulator of ERR-γ expression in the liver. Administration of IL-6 neutralizing antibody to FA-treated mice or of recombinant IL-6 to healthy mice confirms IL-6 as an upstream regulator of hepatic ERR-γ-mediated FGF23 production. A significant (P < 0.001) interconnection between high IL-6 and FGF23 levels as a predictor of AKI in patients that underwent cardiac surgery was also found, suggesting the clinical relevance of the finding. Finally, liver-specific depletion of ERR-γ or treatment with an inverse ERR-γ agonist decreased hepatic FGF23 expression and plasma FGF23 levels in mice with FA-induced AKI. Thus, inverse agonist of ERR-γ may represent a therapeutic strategy to reduce adverse plasma FGF23 levels in AKI.


Asunto(s)
Lesión Renal Aguda/fisiopatología , Factor-23 de Crecimiento de Fibroblastos/metabolismo , Receptores de Estrógenos/metabolismo , Lesión Renal Aguda/metabolismo , Animales , Modelos Animales de Enfermedad , Factor-23 de Crecimiento de Fibroblastos/genética , Ácido Fólico/efectos adversos , Ácido Fólico/farmacología , Interleucina-6/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Receptores Nucleares Huérfanos/metabolismo , Receptores de Estrógenos/genética , Activación Transcripcional
5.
Dev Dyn ; 252(6): 761-769, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36825302

RESUMEN

BACKGROUND: The Bone morphogenetic protein 4 (BMP4) precursor protein is cleaved at two sites to generate an active ligand and inactive prodomain. The ligand and prodomain form a noncovalent complex following the first cleavage, but dissociate after the second cleavage. Transient formation of this complex is essential to generate a stable ligand. Fibrillins (FBNs) bind to the prodomains of BMPs, and can regulate the activity of some ligands. Whether FBNs regulate BMP4 activity is unknown. RESULTS: Mice heterozygous for a null allele of Bmp4 showed incompletely penetrant kidney defects and females showed increased mortality between postnatal day 6 and 8. Removal of one copy of Fbn1 did not rescue or enhance kidney defects or lethality. The lungs of Fbn1+/- females had enlarged airspaces that were unchanged in Bmp4+/- ;Fbn1+/- mice. Additionally, removal of one or both alleles of Fbn1 had no effect on steady state levels of BMP4 ligand or on BMP activity in postnatal lungs. CONCLUSIONS: These findings do not support the hypothesis that FBN1 plays a role in promoting BMP4 ligand stability or signaling, nor do they support the alternative hypothesis that FBN1 sequesters BMP4 in a latent form, as is the case for other BMP family members.


Asunto(s)
Proteínas Morfogenéticas Óseas , Riñón , Femenino , Ratones , Animales , Proteína Morfogenética Ósea 4/genética , Proteína Morfogenética Ósea 4/metabolismo , Ligandos , Proteínas Morfogenéticas Óseas/metabolismo , Alelos , Riñón/metabolismo , Proteína Morfogenética Ósea 7 , Proteína Morfogenética Ósea 2
6.
Small ; 19(21): e2300250, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36828790

RESUMEN

Bioelectrodes have been developed to efficiently mediate electrical signals of biological systems as stimulators and recording devices. Recently, conductive hydrogels have garnered great attention as emerging materials for bioelectrode applications because they can permit intimate/conformal contact with living tissues and tissue-like softness. However, administration and control over the in vivo lifetime of bioelectrodes remain challenges. Here, injectable conductive hydrogels (ICHs) with tunable degradability as implantable bioelectrodes are developed. ICHs were constructed via thiol-ene reactions using poly(ethylene glycol)-tetrathiol and thiol-functionalized reduced graphene oxide with either hydrolyzable poly(ethylene glycol)-diacrylate or stable poly(ethylene glycol)-dimaleimide, the resultant hydrogels of which are degradable and nondegradable, respectively. The ICH electrodes had conductivities of 21-22 mS cm-1 and Young's moduli of 15-17 kPa, and showed excellent cell and tissue compatibility. The hydrolyzable conductive hydrogels disappeared 3 days after in vivo administration, while the stable conductive hydrogels maintained their shapes for up to 7 days. Our proof-of-concept studies reveal that electromyography signals with significantly improved sensitivity from rats could be obtained from the injected ICH electrodes compared to skin electrodes and injected nonconductive hydrogel electrodes. The ICHs, offering convenience in use, controllable degradation and excellent signal transmission, will have great potential to develop various bioelectronics devices.


Asunto(s)
Hidrogeles , Polietilenglicoles , Ratas , Animales , Prótesis e Implantes , Conductividad Eléctrica
7.
Small ; 19(16): e2206238, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36617520

RESUMEN

SiOx is a promising next-generation anode material for lithium-ion batteries. However, its commercial adoption faces challenges such as low electrical conductivity, large volume expansion during cycling, and low initial Coulombic efficiency. Herein, to overcome these limitations, an eco-friendly in situ methodology for synthesizing carbon-containing mesoporous SiOx nanoparticles wrapped in another carbon layers is developed. The chemical reactions of vinyl-terminated silanes are designed to be confined inside the cationic surfactant-derived emulsion droplets. The polyvinylpyrrolidone-based chemical functionalization of organically modified SiO2 nanoparticles leads to excellent dispersion stability and allows for intact hybridization with graphene oxide sheets. The formation of a chemically reinforced heterointerface enables the spontaneous generation of mesopores inside the thermally reduced SiOx nanoparticles. The resulting mesoporous SiOx -based nanocomposite anodes exhibit superior cycling stability (≈100% after 500 cycles at 0.5 A g-1 ) and rate capability (554 mAh g-1 at 2 A g-1 ), elucidating characteristic synergetic effects in mesoporous SiOx -based nanocomposite anodes. The practical commercialization potential with a significant enhancement in initial Coulombic efficiency through a chemical prelithiation reaction is also presented. The full cell employing the prelithiated anode demonstrated more than 2 times higher Coulombic efficiency and discharge capacity compared to the full cell with a pristine anode.

8.
Proc Natl Acad Sci U S A ; 117(23): 12991-12999, 2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32439710

RESUMEN

Malignant melanoma has one of the highest mortality rates of any cancer because of its aggressive nature and high metastatic potential. Clinical staging of the disease at the time of diagnosis is very important for the prognosis and outcome of melanoma treatment. In this study, we designed and synthesized the 18F-labeled pyridine-based benzamide derivatives N-(2-(dimethylamino)ethyl)-5-[18F]fluoropicolinamide ([18F]DMPY2) and N-(2-(dimethylamino)ethyl)-6-[18F]fluoronicotinamide ([18F]DMPY3) to detect primary and metastatic melanoma at an early stage and evaluated their performance in this task. [18F]DMPY2 and [18F]DMPY3 were synthesized by direct radiofluorination of the bromo precursor, and radiochemical yields were ∼15-20%. Cell uptakes of [18F]DMPY2 and [18F]DMPY3 were >103-fold and 18-fold higher, respectively, in B16F10 (mouse melanoma) cells than in negative control cells. Biodistribution studies revealed strong tumor uptake and retention of [18F]DMPY2 (24.8% injected dose per gram of tissue [ID/g] at 60 min) and [18F]DMPY3 (11.7%ID/g at 60 min) in B16F10 xenografts. MicroPET imaging of both agents demonstrated strong tumoral uptake/retention and rapid washout, resulting in excellent tumor-to-background contrast in B16F10 xenografts. In particular, [18F]DMPY2 clearly visualized almost all metastatic lesions in lung and lymph nodes, with excellent image quality. [18F]DMPY2 demonstrated a significantly higher tumor-to-liver ratio than [18F]fluorodeoxyglucose ([18F]FDG) and the previously reported benzamide tracers N-[2-(diethylamino)-ethyl]-5-[18F]fluoropicolinamide ([18F]P3BZA) and N-[2-(diethylamino)-ethyl]-4-[18F]fluorobenzamide ([18F]FBZA) in B16F10-bearing or SK-MEL-3 (human melanoma)-bearing mice. In conclusion, [18F]DMPY2 might have strong potential for the diagnosis of early stage primary and metastatic melanoma using positron emission tomography (PET).


Asunto(s)
Melanoma/diagnóstico por imagen , Imagen Molecular/métodos , Tomografía de Emisión de Positrones/métodos , Radiofármacos/administración & dosificación , Neoplasias Cutáneas/diagnóstico por imagen , Animales , Línea Celular Tumoral , Radioisótopos de Flúor/administración & dosificación , Humanos , Ratones , Ácidos Picolínicos/administración & dosificación , Radiofármacos/química , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Int J Mol Sci ; 24(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37240145

RESUMEN

Epithelial-to-mesenchymal transition (EMT) plays a critical role in the development and progression of lung cancer by promoting its invasiveness and metastasis. Using integrative analyses of the public lung cancer database, we found that the expression levels of the tight junction proteins, zonula occluden (ZO)-1 and ZO-2, were lower in lung cancer tissues, including both lung adenocarcinoma and lung squamous cell carcinoma than in normal lung tissues analyzed using The Cancer Genome Atlas (TCGA). Although the ectopic expression or knockdown of ZO-1 and ZO-2 did not affect the growth of lung cancer cells, they significantly regulated cell migration and invasion. When M0 macrophages were co-cultured with ZO-1 or ZO-2 knockdown Calu-1 cells, M2-like polarization was efficiently induced. Conversely, co-culture of M0 THP-1 cells with A549 cells stably expressing ZO-1 or ZO-2 significantly reduced M2 differentiation. We also identified G protein subunit alpha q (GNAQ) as a potential ZO-1- and ZO-2-specific activator through analysis of correlated genes with the TCGA lung cancer database. Our results suggest that the GNAQ-ZO-1/2 axis may play a tumor-suppressive role in lung cancer development and progression and highlight ZO-1 and ZO-2 as key EMT- and tumor microenvironment-suppressive proteins. These findings provide new insights for the development of targeted therapies for lung cancer.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Uniones Estrechas/metabolismo , Microambiente Tumoral/genética , Neoplasias Pulmonares/genética , Transición Epitelial-Mesenquimal/genética , Proteína de la Zonula Occludens-1/genética , Proteína de la Zonula Occludens-1/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo
10.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36901700

RESUMEN

Cancer-associated fibroblasts (CAFs) contribute to tumor progression, and microRNAs (miRs) play an important role in regulating the tumor-promoting properties of CAFs. The objectives of this study were to clarify the specific miR expression profile in CAFs of hepatocellular carcinoma (HCC) and identify its target gene signatures. Small-RNA-sequencing data were generated from nine pairs of CAFs and para-cancer fibroblasts isolated from human HCC and para-tumor tissues, respectively. Bioinformatic analyses were performed to identify the HCC-CAF-specific miR expression profile and the target gene signatures of the deregulated miRs in CAFs. Clinical and immunological implications of the target gene signatures were evaluated in The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA_LIHC) database using Cox regression and TIMER analysis. The expressions of hsa-miR-101-3p and hsa-miR-490-3p were significantly downregulated in HCC-CAFs. Their expression in HCC tissue gradually decreased as HCC stage progressed in the clinical staging analysis. Bioinformatic network analysis using miRWalks, miRDB, and miRTarBase databases pointed to TGFBR1 as a common target gene of hsa-miR-101-3p and hsa-miR-490-3p. TGFBR1 expression was negatively correlated with miR-101-3p and miR-490-3p expression in HCC tissues and was also decreased by ectopic miR-101-3p and miR-490-3p expression. HCC patients with TGFBR1 overexpression and downregulated hsa-miR-101-3p and hsa-miR-490-3p demonstrated a significantly poorer prognosis in TCGA_LIHC. TGFBR1 expression was positively correlated with the infiltration of myeloid-derived suppressor cells, regulatory T cells, and M2 macrophages in a TIMER analysis. In conclusion, hsa-miR-101-3p and hsa-miR-490-3p were substantially downregulated miRs in CAFs of HCC, and their common target gene was TGFBR1. The downregulation of hsa-miR-101-3p and hsa-miR-490-3p, as well as high TGFBR1 expression, was associated with poor clinical outcome in HCC patients. In addition, TGFBR1 expression was correlated with the infiltration of immunosuppressive immune cells.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Fibroblastos Asociados al Cáncer/metabolismo , MicroARNs/genética , Regulación Neoplásica de la Expresión Génica , Proliferación Celular/genética
11.
Sensors (Basel) ; 22(20)2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36298353

RESUMEN

With the advancement in next-generation communication technologies, the so-called Tactile Internet is getting more attention due to its smart applications, such as haptic-enabled teleoperation systems. The stringent requirements such as delay, jitter, and packet loss of these delay-sensitive and loss-intolerant applications make it more challenging to ensure the Quality of Service (QoS) and Quality of Experience (QoE). In this regard, different haptic codec and control schemes were proposed for QoS and QoE provisioning in the Tactile Internet. However, they maximize the QoE while degrading the system's stability under varying delays and high packet rates. In this paper, we present a reinforcement learning-based Intelligent Tactile Edge (ITE) framework to ensure both transparency and stability of teleoperation systems with high packet rates and variable time delay communication networks. The proposed ITE first estimates the network challenges, including communication delay, jitter, and packet loss, and then utilizes a Q-learning algorithm to select the optimal haptic codec scheme to reduce network load. The proposed framework aims to explore the optimal relationship between QoS and QoE parameters and make the tradeoff between stability and transparency during teleoperations. The simulation result indicates that the proposed strategy chooses the optimal scheme under different network impairments corresponding to the congestion level in the communication network while improving the QoS and maximizing the QoE. The end-to-end performance of throughput (1.5 Mbps) and average RTT (70 ms) during haptic communication is achieved with a learning rate and discounted factor value of 0.5 and 0.8, respectively. The results indicate that the communication system can successfully achieve the QoS and QoE requirements by employing the proposed ITE framework.


Asunto(s)
Algoritmos , Redes de Comunicación de Computadores , Simulación por Computador , Inteligencia
12.
Sensors (Basel) ; 21(11)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34070608

RESUMEN

Recent advancements in telecommunications and the tactile Internet have paved the way for studying human senses through haptic technology. Haptic technology enables tactile sensations and control using virtual reality (VR) over a network. Researchers are developing various haptic devices to allow for real-time tactile sensation, which can be used in various industries, telesurgery, and other mission-critical operations. One of the main criteria of such devices is extremely low latency, as low as 1 ms. Although researchers are attempting to develop haptic devices with low latency, there remains a need to improve latency and robustness to hand sizes. In this paper, a low-latency haptic open glove (LLHOG) based on a rotary position sensor and min-max scaling (MMS) filter is proposed to realize immersive VR interaction. The proposed device detects finger flexion/extension and adduction/abduction motions using two position sensors located in the metacarpophalangeal (MCP) joint. The sensor data are processed using an MMS filter to enable low latency and ensure high accuracy. Moreover, the MMS filter is used to process object handling control data to enable hand motion-tracking. Its performance is evaluated in terms of accuracy, latency, and robustness to finger length variations. We achieved a very low processing delay of 145.37 µs per finger and overall hand motion-tracking latency of 4 ms. Moreover, we tested the proposed glove with 10 subjects and achieved an average mean absolute error (MAE) of 3.091∘ for flexion/extension, and 2.068∘ for adduction/abduction. The proposed method is therefore superior to the existing methods in terms of the above factors for immersive VR interaction.


Asunto(s)
Realidad Virtual , Dedos , Mano , Humanos , Movimiento , Tacto
13.
Molecules ; 26(20)2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34684684

RESUMEN

Memory deterioration in Alzheimer's disease (AD) is thought to be underpinned by aberrant amyloid ß (Aß) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3ß (p-GSK3ß-S9) and cleaved caspase 3, which are involved in Aß-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Hipocampo/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , ortoaminobenzoatos/farmacología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Avena/química , Modelos Animales de Enfermedad , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hipocampo/metabolismo , Potenciación a Largo Plazo/fisiología , Masculino , Ratones , Ratones Transgénicos , Plasticidad Neuronal , Extractos Vegetales/farmacología
14.
J Anesth ; 35(1): 86-92, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33221959

RESUMEN

PURPOSE: Many studies have been published on the beneficial effects of oral carbohydrate solutions (OCS) administered prior to surgery. However, the risk of pulmonary aspiration cannot be excluded in all patients undergoing anesthesia. But, there are few studies on the safety of OCS at lung aspiration. METHODS: Experiments were conducted with mice (Nine- to ten-week-old male BALB/c mice weighted 23-26 g). Lung aspiration was performed by intratracheal administration of OCS and its major constituents, fructose and maltodextrin. Bronchoalveolar lavage fluid (BALF) was collected 3 and 24 h after lung aspiration. The level of Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and macrophage inflammatory protein-2 (MIP-2) were measured in BALF. The total white blood cell, neutrophil counts, wet to dry ratio and histological examination were performed in BALF and lung tissue, respectively, at 24 h after aspiration. RESULTS: The OCS increased the level of TNF-α, IL-6 and MIP-2 at 3 h and the neutrophil count at 24 h in BALFs, compared to a phosphate-buffered saline (PBS) group. The increase in IL-6 level induced by OCS was maintained for 24 h. The OCS also increased the number of white blood cells and the percentage of neutrophils in BALFs. Compared to fructose, maltodextrin significantly increased the production of MIP-2 in BALFs. OCS and maltodextrin also increased neutrophil recruitment in lung tissue. CONCLUSION: Aspiration of OCS may cause inflammation of the lungs. The preoperative use of OCS may require caution under specific clinical conditions, such as patients at risk of lung aspiration.


Asunto(s)
Pulmón , Factor de Necrosis Tumoral alfa , Animales , Líquido del Lavado Bronquioalveolar , Carbohidratos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Neutrófilos
15.
Biochem Biophys Res Commun ; 530(2): 389-395, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32532423

RESUMEN

Recent studies have revealed that protein arginine methyltransferases (PRMTs) are responsible for diverse neurodegenerative diseases. However, their pathophysiological role in dopaminergic neuronal death in Parkinson's disease (PD) has not been evaluated. In this study, we demonstrated that 1-Methyl-4-phenylpyridinium iodide (MPP+), rotenone and paraquat, which cause dopaminergic neuronal cell death, increased PRMT1 expression in dopaminergic cell line. Dopaminergic neuronal cell death was increased by PRMT1 overexpression. MPP+-induced cell death was attenuated by PRMT1 knockdown. Poly (ADP-ribose) polymerase-1 (PARP1) expression and activity, poly-ADP-ribosylation (PARylation), were elevated by MPP+. Moreover, we found that PRMT1 positively regulates nuclear translocation of apoptosis-inducing factor (AIF). Elevated PRMT1 expression was observed in the substantia nigra pars compacta of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-injected mice. Furthermore, MPTP-induced dopaminergic neuronal death was reduced in PRMT1 haploinsufficient (prmt1+/-) mice. These data suggest that PRMT1 is implicated in PARP1/AIF-mediated dopaminergic neuronal cell death, which might be involved in the pathology of PD. Therefore, our results propose PRMT1 as a new target to develop a potential treatment of PD.


Asunto(s)
Neuronas Dopaminérgicas/patología , Enfermedad de Parkinson/patología , Proteína-Arginina N-Metiltransferasas/metabolismo , Animales , Muerte Celular , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Humanos , Masculino , Ratones , Enfermedad de Parkinson/metabolismo , Proteína-Arginina N-Metiltransferasas/análisis
16.
Hepatology ; 70(4): 1262-1279, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30991448

RESUMEN

Histone deacetylase 6 (HDAC6) uniquely serves as a tumor suppressor in hepatocellular carcinogenesis, but the underlying mechanisms leading to tumor suppression are not fully understood. To identify comprehensive microRNAs (miRNAs) regulated by HDAC6 in hepatocellular carcinogenesis, differential miRNA expression analysis of HDAC6-transfected Hep3B cells was performed. Using integrative analyses of publicly available transcriptome data and miRNA target prediction, we selected five candidate miRNAs and, through in vitro functional validation, showed that let-7i-5p specifically suppressed thrombospondin-1 (TSP1) in hepatocellular carcinoma (HCC). Ectopic expression of antisense let-7i-5p (AS-let-7i-5p) inhibited in vitro tumorigenesis of HCC cells. In addition, treatments of partially purified TSP1 from culture cell media (ppTSP1) and recombinant TSP1 (rTSP1) exhibited similar effects with AS-let-7i-5p treatment on the same HCC cells, whereas TSP1 neutralizing antibody treatment significantly attenuated these effects. Notably, treatments of HDAC6 plasmid, AS-let-7i-5p, ppTSP1, and rTSP1 significantly suppressed in vitro angiogenesis and metastatic potential of HCC cells, but the co-treatment of TSP1 antibody specific to cluster of differentiation 47 (CD47) binding domain successfully blocked these effects in the same cells. Furthermore, we demonstrated that recovery of HDAC6 elicited let-7i-5p suppression to de-repress TSP1 expression; therefore, it occupied the CD47 receptor to block CD47-SIRPα-mediated anti-phagocytosis of macrophage in HCC. We also observed that HCC-derived exosomal let-7i-5p suppressed TSP1 of recipient hepatocyte cells. Treatments of HDAC6 plasmid, AS-let-7i-5p, and rTSP1 suppressed tumor incidence as well as tumor growth rates in a spontaneous mouse HCC model. Conclusion: Our findings suggest that the HDAC6-let-7i-5p-TSP1 regulatory pathway suppresses neoplastic and antiphagocytic behaviors of HCC by interacting with cell surface receptor CD47 in HCC and neighboring cells of tumor microenvironment, providing a therapeutic target for the treatment of liver malignancy and metastasis.


Asunto(s)
Antígeno CD47/genética , Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica/genética , Histona Desacetilasa 6/genética , Neoplasias Hepáticas/genética , Trombospondina 1/metabolismo , Análisis de Varianza , Animales , Carcinogénesis/genética , Carcinoma Hepatocelular/patología , Diferenciación Celular/genética , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Modelos Animales de Enfermedad , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Transgénicos , MicroARNs/genética , Fagocitosis/genética , Distribución Aleatoria , Microambiente Tumoral/genética
17.
Rheumatology (Oxford) ; 59(8): 2124-2134, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32087015

RESUMEN

OBJECTIVE: This study was designed to investigate the role of mucosal-associated invariant T (MAIT) cells in gouty arthritis (GA) and their effects on osteoclastogenesis. METHODS: Patients with GA (n = 61), subjects with hyperuricaemia (n = 11) and healthy controls (n = 30) were enrolled in this study. MAIT cells, cytokines, CD69, programmed death-1 (PD-1) and lymphocyte-activation gene 3 (LAG-3) levels were measured by flow cytometry. In vitro osteoclastogenesis experiments were performed using peripheral blood mononuclear cells in the presence of M-CSF and RANK ligand. RESULTS: Circulating MAIT cell levels were significantly reduced in GA patients. However, their capacities for IFN-γ, IL-17 and TNF-α production were preserved. Expression levels of CD69, PD-1 and LAG-3 in MAIT cells were found to be elevated in GA patients. In particular, CD69 expression in circulating MAIT cells was increased by stimulation with MSU crystals, suggesting that deposition of MSU crystals might contribute to MAIT cell activation. Interestingly, MAIT cells were found to be accumulated in synovial fluid and infiltrated into gouty tophus tissues within joints. Furthermore, activated MAIT cells secreted pro-resorptive cytokines (i.e. IL-6, IL-17 and TNF-α) and facilitated osteoclastogenesis. CONCLUSION: This study demonstrates that circulating MAIT cells are activated and numerically deficient in GA patients. In addition, MAIT cells have the potential to migrate to inflamed tissues and induce osteoclastogenesis. These findings provide an important role of MAIT cells in the pathogenesis of inflammation and bone destruction in GA patients.


Asunto(s)
Artritis Gotosa/metabolismo , Hiperuricemia/metabolismo , Células T Invariantes Asociadas a Mucosa/metabolismo , Osteogénesis/fisiología , Adulto , Anciano , Movimiento Celular/fisiología , Citocinas/metabolismo , Femenino , Citometría de Flujo , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad
18.
Plant Physiol ; 180(4): 1912-1929, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31171578

RESUMEN

Until they become photoautotrophic juvenile plants, seedlings depend upon the reserves stored in seed tissues. These reserves must be mobilized and metabolized, and their breakdown products must be distributed to the different organs of the growing seedling. Here, we investigated the mobilization of soybean (Glycine max) seed reserves during seedling growth by initially constructing a genome-scale stoichiometric model for this important crop plant and then adapting the model to reflect metabolism in the cotyledons and hypocotyl/root axis (HRA). A detailed analysis of seedling growth and alterations in biomass composition was performed over 4 d of postgerminative growth and used to constrain the stoichiometric model. Flux balance analysis revealed marked differences in metabolism between the two organs, together with shifts in primary metabolism occurring during different periods postgermination. In particular, from 48 h onward, cotyledons were characterized by the oxidation of fatty acids to supply carbon for the tricarboxylic acid cycle as well as production of sucrose and glutamate for export to the HRA, while the HRA was characterized by the use of a range of imported amino acids in protein synthesis and catabolic processes. Overall, the use of flux balance modeling provided new insight into well-characterized metabolic processes in an important crop plant due to their analysis within the context of a metabolic network and reinforces the relevance of the application of this technique to the analysis of complex plant metabolic systems.


Asunto(s)
Glycine max/metabolismo , Plantones/metabolismo , Carbono/metabolismo , Cotiledón/genética , Cotiledón/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácido Glutámico/metabolismo , Hipocótilo/genética , Hipocótilo/metabolismo , Plantones/genética , Glycine max/genética , Sacarosa/metabolismo
19.
J Korean Med Sci ; 35(33): e310, 2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32830471

RESUMEN

With the rapidly spreading coronavirus disease 2019 (COVID-19) pandemic over the past few months, the world is facing an unprecedented crisis. Innumerable lives have been lost to this novel infectious disease, the nature of which supersedes conventional medical understanding. The COVID-19 pandemic is not just a global health crisis, several aspects of life in the post-COVID-19 era are also being contemplated. Experts in unison are warning that the upcoming changes in all areas of life could potentially be far more drastic than ever experienced in the entire human civilization. The medical community is no exception, and therefore, personnel involved in forensic medicine also need to be adequately prepared for the future. Forensic medicine is a branch of medicine dedicated to one of the most important stages of the human lifecycle and has always been at the forefront in times of unprecedented social change. The autopsy, one of the most important tools of forensic medicine, is also useful to infectious diseases because it identifies the causal relationship between death and infection, reveals medical and epidemiological knowledge, and provides objective evidence for legal disputes. We present new autopsy guidelines in forensic medicine, formulated based on the various infectious diseases that we presently live with and may encounter in the future. In formulation of these guidelines several considerations have been taken into account, namely, the role forensic pathologists should play in the post-COVID-19 era and the necessary preparations as well as the support needed from society to fulfill that role. The present COVID-19 outbreak should be a starting point for formulating improvements in current practices in forensic science, including autopsy biosafety practices and the medicolegal death investigation system.


Asunto(s)
Autopsia/métodos , Betacoronavirus , Infecciones por Coronavirus/patología , Neumonía Viral/patología , Guías de Práctica Clínica como Asunto , COVID-19 , Contención de Riesgos Biológicos , Infecciones por Coronavirus/prevención & control , Medicina Legal , Recursos en Salud , Humanos , Pandemias/prevención & control , Equipo de Protección Personal , Neumonía Viral/prevención & control , República de Corea , SARS-CoV-2
20.
Sensors (Basel) ; 20(18)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957686

RESUMEN

Hybrid pre-coding strategies are considered as a potential solution for combating path loss experienced by Massive MIMO systems operating at millimeter wave frequencies. The partially connected structure is preferred over the fully connected structure due to smaller computational complexity. In order to improve the spectral efficiency of a partially connected hybrid pre-coding architecture, which is one of the requirements of future 5G/B5G systems, this work proposes the application of evolutionary algorithms for joint computation of RF and the digital pre-coder. The evolutionary algorithm based scheme jointly evaluates the RF and digital pre-coder for a partially connected hybrid structure by taking into account the current RF chain for computations and therefore it is not based on interference cancellation from all other RF chains as in the case of successive interference cancellation (SIC). The evolutionary algorithm, i.e., Artificial Bee Colony (BEE) based pre-coding scheme outperforms other popular evolutionary algorithms as well as the SIC based pre-coding scheme in terms of spectral efficiency. In addition, the proposed algorithm is not overly sensitive to variations in channel conditions.

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