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1.
Nat Commun ; 15(1): 6964, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138195

RESUMEN

Though RNAi and RNA-splicing machineries are involved in regulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication, their precise roles in coronavirus disease 2019 (COVID-19) pathogenesis remain unclear. Herein, we show that decreased RNAi component (Dicer and XPO5) and splicing factor (SRSF3 and hnRNPA3) expression correlate with increased COVID-19 severity. SARS-CoV-2 N protein induces the autophagic degradation of Dicer, XPO5, SRSF3, and hnRNPA3, inhibiting miRNA biogenesis and RNA splicing and triggering DNA damage, proteotoxic stress, and pneumonia. Dicer, XPO5, SRSF3, and hnRNPA3 knockdown increases, while their overexpression decreases, N protein-induced pneumonia's severity. Older mice show lower expression of Dicer, XPO5, SRSF3, and hnRNPA3 in their lung tissues and exhibit more severe N protein-induced pneumonia than younger mice. PJ34, a poly(ADP-ribose) polymerase inhibitor, or anastrozole, an aromatase inhibitor, ameliorates N protein- or SARS-CoV-2-induced pneumonia by restoring Dicer, XPO5, SRSF3, and hnRNPA3 expression. These findings will aid in developing improved treatments for SARS-CoV-2-associated pneumonia.


Asunto(s)
COVID-19 , Carioferinas , Ribonucleasa III , SARS-CoV-2 , Factores de Empalme Serina-Arginina , Animales , Factores de Empalme Serina-Arginina/metabolismo , Factores de Empalme Serina-Arginina/genética , Humanos , Ribonucleasa III/metabolismo , Ribonucleasa III/genética , SARS-CoV-2/genética , COVID-19/metabolismo , COVID-19/virología , COVID-19/genética , Ratones , Carioferinas/metabolismo , Carioferinas/genética , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Regulación hacia Abajo , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Masculino , Femenino , MicroARNs/genética , MicroARNs/metabolismo , Empalme del ARN , Autofagia/genética , Daño del ADN , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B
3.
Chemosphere ; 358: 141980, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38670508

RESUMEN

Generally, the pH of fluorinated groundwater or many industrial wastewater is neutral, while the majority of metal-modified adsorbents can work efficiently only under acidic conditions. In this study, we synthesized a novel hybrid adsorbent, Mg-Zr-D213, by loading nano-Mg/Zr binary metal (hydrogen) oxides in a strong-base anion exchanger, D213, to enhance the adsorption of fluoride from neutral water. Mg-Zr-D213 exhibited a better fluoride-removal capacity in neutral water than monometallic modified resins. Under the interference of competing anions and coexisting organic acids, Mg-Zr-D213 exhibited superior selectivity. The Langmuir model indicated that the fitted maximum sorption capacity of Mg-Zr-D213 was 41.38 mg/g. The results of column experiments showed that the effective treatment volume of Mg-Zr-D213 was 8-16-times higher than that of D213 for both synthetic groundwater and actual industrial wastewater, and that NaOH-NaCl eluent could effectively recover more than 95% of fluoride. Adsorption experiments with Mg/Zr metal (hydrogen) oxide particles and D213 separately demonstrated a synergistic effect between -N+(CH3)3 and Mg/Zr metal (hydrogen) oxide particles. The ligand exchange or metal-ligand interaction of Mg/Zr metal (hydrogen) oxide particles on fluoride was further demonstrated via X-ray photoelectron spectroscopy. Overall, Mg-Zr-D213 has great potential for enhanced fluoride removal in neutral water.


Asunto(s)
Fluoruros , Agua Subterránea , Nanopartículas del Metal , Contaminantes Químicos del Agua , Purificación del Agua , Circonio , Fluoruros/química , Adsorción , Circonio/química , Contaminantes Químicos del Agua/química , Nanopartículas del Metal/química , Agua Subterránea/química , Purificación del Agua/métodos , Aniones/química , Aguas Residuales/química , Óxidos/química , Concentración de Iones de Hidrógeno
4.
Mol Phylogenet Evol ; 196: 108084, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38688440

RESUMEN

The tribe Collabieae (Epidendroideae, Orchidaceae) comprises approximately 500 species. Generic delimitation within Collabieae are confusing and phylogenetic interrelationships within the Collabieae have not been well resolved. Plastid genomes and nuclear internal transcribed spacer (ITS) sequences were used to estimate the phylogenetic relationships, ancestral ranges, and diversification rates of Collabieae. The results showed that Collabieae was subdivided into nine clades with high support. We proposed to combine Ancistrochilus and Pachystoma into Spathoglottis, merge Collabium and Chrysoglossum into Diglyphosa, and separate Pilophyllum and Hancockia as distinctive genera. The diversification of the nine clades of Collabieae might be associated with the uplift of the Himalayas during the Late Oligocene/Early Miocene. The enhanced East Asian summer monsoon in the Late Miocene may have promoted the rapid diversification of Collabieae at a sustained high diversification rate. The increased size of terrestrial pseudobulbs may be one of the drivers of Collabieae diversification. Our results suggest that the establishment and development of evergreen broadleaved forests facilitated the diversification of Collabieae.


Asunto(s)
Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/clasificación , Bosques , Genoma de Plastidios/genética , Filogeografía , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADN , Asia , ADN de Plantas/genética
5.
STAR Protoc ; 5(2): 102998, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38573862

RESUMEN

We recently identified a class of small cytosolic double-stranded DNA (scDNA) approximately 20-40 bp in size in human and mouse cells. Here, we present a protocol for scDNA isolation from cultured murine cells. We describe steps for cytosolic compartment separation, DNA isolation in the cytosolic fraction using phenol-chloroform extraction, and ethanol precipitation. We then detail procedures for denaturing purified cytosolic DNA through urea polyacrylamide gel electrophoresis and obtaining scDNA in the cytosolic DNA fraction via gel purification. For complete details on the use and execution of this protocol, please refer to Liu et al.1.


Asunto(s)
Citosol , ADN , Animales , Ratones , ADN/aislamiento & purificación , Citosol/metabolismo , Citosol/química , Células Cultivadas , Electroforesis en Gel de Poliacrilamida/métodos
7.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38139421

RESUMEN

WNK (With No Lysine) kinases are members of serine/threonine protein kinase family, which lack conserved a catalytic lysine (K) residue in protein kinase subdomain II and this residue is replaced by either asparagine, serine, or glycine residues. They are involved in various physiological regulations of flowering time, circadian rhythms, and abiotic stresses in plants. In this study, we identified the WNK gene family in two species of Acorus, and analyzed their phylogenetic relationship, physiochemical properties, subcellular localization, collinearity, and cis-elements. The results showed twenty-two WNKs in two Acorus (seven in Ac. gramineus and fifteen in Ac. calamus) have been identified and clustered into five main clades phylogenetically. Gene structure analysis showed all WNKs possessed essential STKc_WNK or PKc_like superfamily domains, and the gene structures and conserved motifs of the same clade were similar. All the WNKs harbored a large number of light response elements, plant hormone signaling elements, and stress resistance elements. Through a collinearity analysis, two and fourteen segmental duplicated gene pairs were identified in the Ac. gramineus and Ac. calamus, respectively. Moreover, we observed tissue-specificity of WNKs in Acorus using transcriptomic data, and their expressions in response to salt stress and cold stress were analyzed by qRT-PCR. The results showed WNKs are involved in the regulation of abiotic stresses. There were significant differences in the expression levels of most of the WNKs in the leaves and roots of Acorus under salt stress and cold stress, among which two members in Ac. gramineus (AgWNK3 and AgWNK4) and two members in Ac. calamus (AcWNK8 and AcWNK12) were most sensitive to stress. In summary, this paper will significantly contribute to the understanding of WNKs in monocots and thus provide a set up for functional genomics studies of WNK protein kinases.


Asunto(s)
Acorus , Acorus/metabolismo , Filogenia , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Serina/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
Autophagy ; : 1-3, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38013411

RESUMEN

The CGAS (cyclic GMP-AMP synthase)-STING1 (stimulator of interferon response cGAMP interactor 1) pathway is an important innate immune pathway that induces proinflammatory cytokine production following stimulation with dsDNA > 45 bp. We recently identified a class of ~ 20-40 bp small cytosolic dsDNA (scDNA) that blocks CGAS-STING1 activation. In this punctum, we discuss the mechanism underlying the inhibition of CGAS-STING1 activation via scDNA. scDNA binds to CGAS but cannot activate its enzymatic activity. It competes with dsDNA > 45 bp for binding with CGAS to inhibit CGAS-STING1 activation. Moreover, scDNA activates macroautophagy/autophagy and induces the autophagic degradation of STING1 and long dsDNA. Autophagy then increases scDNA levels, driving a feedback loop that accelerates the degradation of STING1 and long cytosolic dsDNA. These findings reveal that mutual communication between scDNA and autophagy inhibits CGAS-STING1 activation following stimulation with dsDNA > 45 bp.

9.
Sci Rep ; 13(1): 14820, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684297

RESUMEN

Carbon doping in GaN-on-Silicon (Si) epitaxial layers is an essential way to reduce leakage current and improve breakdown voltage. However, complicated occupy forms caused by carbon lead to hard analysis leakage/breakdown mechanisms of GaN-on-Si epitaxial layers. In this paper, we demonstrate the space charge distribution and intensity in GaN-on-Si epitaxial layers from 0 to 448 V by simulation. Depending on further monitoring of the trapped charge density of CN and CGa in carbon-doped GaN at 0.1 µm, 0.2 µm, 1.8 µm and 1.9 µm from unintentionally doped GaN/carbon-doped GaN interface, we discuss the relationship between space charge and plateau, breakdown at CN concentrations from 6 × 1016 cm-3 to 6 × 1018 cm-3. The results show that CN in different positions of carbon-doped GaN exhibits significantly different capture and release behaviors. By utilizing the capture and release behavior differences of CN at different positions in carbon-doped GaN, the blocking effect of space charge at unintentionally doped GaN/carbon-doped GaN interface on electron conduction was demonstrated. The study would help to understand the behavior of CN and CGa in GaN-on-Si epitaxial layers and more accurate control of CN and CGa concentration at different positions in carbon-doped GaN to improve GaN-on-Si device performance.

10.
Macromol Rapid Commun ; 44(20): e2300336, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37571924

RESUMEN

Heterogeneous photocatalysts have attracted extensive attention in photo-induced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization due to their remarkable advantages such as easy preparation, tunable photoelectric properties, and recyclability. In this study, zinc (II) 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (ZnTAPP)-based poly-porphyrin nanoparticles (PTAPP-Zn) are constructed by an emulsion-directed approach. It is investigated as a heterogeneous photocatalyst for PET-RAFT polymerization of various methacrylate monomers under visible light exposure, and the reactions show refined polymerization control with high monomer conversions. Furthermore, it is demonstrated that the PTAPP-Zn nanoparticles with the larger pore size enhance photocatalytic activity in PET-RAFT polymerization. In addition, the capabilities of oxygen tolerance and temporal control are demonstrated and PTAPP-Zn particles can be easily recycled and reused without an obvious decrease in catalytic efficiency.


Asunto(s)
Nanopartículas , Porfirinas , Emulsiones , Polimerizacion , Tomografía de Emisión de Positrones
11.
Biomed Pharmacother ; 165: 115267, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37542851

RESUMEN

Cardiac ventricular arrhythmia triggered by acute myocardial infarction (AMI) is a major cause of sudden cardiac death. We have reported previously that an increased serum level of circular RNA CDR1as is a potential biomarker of AMI. However, the possible role of CDR1as in post-infarct arrhythmia remains unclear. This study in MI mice investigated the effects and underlying mechanism of CDR1as in ventricular arrhythmias associated with MI. We showed that knockdown of CDR1as abbreviated the duration of the abnormally prolonged QRS complex and QTc intervals and decreased susceptibility to ventricular arrhythmias. Optical mapping demonstrated knockdown of CDR1as also reduced post-infarct arrhythmia by increasing the conduction velocity and decreasing dispersion of repolarization. Mechanistically, CDR1as led to the depletion of NAD+ and caused mitochondrial dysfunction by directly targeting the NAMPT protein and repressing its expression. Moreover, CDR1as aggravated dysregulation of the NaV1.5 and Kir6.2 channels in cardiomyocytes, a change which was alleviated by the replenishment of NAD+. These findings suggest that anti-CDR1as is a potential therapeutic approach for ischemic arrhythmias.


Asunto(s)
Infarto del Miocardio , NAD , Ratones , Animales , Nicotinamida Fosforribosiltransferasa/genética , Arritmias Cardíacas/etiología , Muerte Súbita Cardíaca/etiología
12.
Cell Rep ; 42(8): 112852, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37481718

RESUMEN

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway is a major mediator of inflammation following stimulation with >45 bp double-stranded DNA (dsDNA). Herein, we identify a class of ∼20-40 bp small cytosolic dsDNA (scDNA) molecules that compete with long dsDNA (200-1,500 bp herring testis [HT]-DNA) for binding to cGAS, thus repressing HT-DNA-induced cGAS activation. The scDNA promotes cGAS and Beclin-1 interaction, releasing Rubicon, a negative regulator of phosphatidylinositol 3-kinase class III (PI3KC3), from the Beclin-1-PI3KC3 complex. This leads to PI3KC3 activation and induces autophagy, causing degradation of STING and long cytosolic dsDNA. Moreover, DNA damage decreases, and autophagy inducers increase scDNA levels. scDNA transfection and treatment with autophagy inducers attenuate DNA damage-induced cGAS activation. Thus, scDNA molecules serve as effective brakes for cGAS activation, preventing excessive inflammatory cytokine production following DNA damage. Our findings may have therapeutic implications for cytosolic DNA-associated inflammatory diseases.


Asunto(s)
ADN , Proteínas de la Membrana , Masculino , Humanos , Beclina-1 , Proteínas de la Membrana/metabolismo , ADN/metabolismo , Nucleotidiltransferasas/metabolismo , Fosfatidilinositol 3-Quinasa , Autofagia
13.
Med Oncol ; 40(8): 217, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37393403

RESUMEN

FAM50A encodes a nuclear protein involved in mRNA processing; however, its role in cancer development remains unclear. Herein, we conducted an integrative pan-cancer analysis using The Cancer Genome Atlas, Genotype-Tissue Expression, and the Clinical Proteomic Tumor Analysis Consortium databases. Based on the gene expression data from TCGA and GTEx databases, we compared FAM50A mRNA levels in 33 types of human cancer tissues to those in corresponding normal tissues and found that FAM50A mRNA level was upregulated in 20 of the 33 types of common cancer tissues. Then, we compared the DNA methylation status of the FAM50A promoter in tumor tissues to that in corresponding normal tissues. FAM50A upregulation was accompanied by promoter hypomethylation in 8 of the 20 types of tumor tissues, suggesting that promoter hypomethylation contributes to the upregulation of FAM50A in these cancer tissues. Elevated FAM50A expression in 10 types of cancer tissues was associated with poor prognosis in patients with cancer. FAM50A expression was positively correlated with CD4+ T-lymphocyte and dendritic cell infiltration in cancer tissues but was negatively correlated with CD8+ T-cell infiltration in cancer tissues. FAM50A knockdown caused DNA damage, induced interferon beta and interleukin-6 expression, and repressed the proliferation, invasion, and migration of cancer cells. Our findings indicate that FAM50A might be useful in cancer detection, reveal insights into its role in cancer development, and may contribute to the development of cancer diagnostics and treatments.


Asunto(s)
Neoplasias , Proteómica , Humanos , Regulación hacia Arriba , Activación Transcripcional , Neoplasias/genética , Linfocitos T CD4-Positivos , Proteínas de Unión al ADN , Proteínas de Unión al ARN
14.
BMC Biol ; 21(1): 134, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280593

RESUMEN

BACKGROUND: Sapria himalayana (Rafflesiaceae) is an endoparasitic plant characterized by a greatly reduced vegetative body and giant flowers; however, the mechanisms underlying its special lifestyle and greatly altered plant form remain unknown. To illustrate the evolution and adaptation of S. himalayasna, we report its de novo assembled genome and key insights into the molecular basis of its floral development, flowering time, fatty acid biosynthesis, and defense responses. RESULTS: The genome of S. himalayana is ~ 1.92 Gb with 13,670 protein-coding genes, indicating remarkable gene loss (~ 54%), especially genes involved in photosynthesis, plant body, nutrients, and defense response. Genes specifying floral organ identity and controlling organ size were identified in S. himalayana and Rafflesia cantleyi, and showed analogous spatiotemporal expression patterns in both plant species. Although the plastid genome had been lost, plastids likely biosynthesize essential fatty acids and amino acids (aromatic amino acids and lysine). A set of credible and functional horizontal gene transfer (HGT) events (involving genes and mRNAs) were identified in the nuclear and mitochondrial genomes of S. himalayana, most of which were under purifying selection. Convergent HGTs in Cuscuta, Orobanchaceae, and S. himalayana were mainly expressed at the parasite-host interface. Together, these results suggest that HGTs act as a bridge between the parasite and host, assisting the parasite in acquiring nutrients from the host. CONCLUSIONS: Our results provide new insights into the flower development process and endoparasitic lifestyle of Rafflesiaceae plants. The amount of gene loss in S. himalayana is consistent with the degree of reduction in its body plan. HGT events are common among endoparasites and play an important role in their lifestyle adaptation.


Asunto(s)
Genoma Mitocondrial , Transferencia de Gen Horizontal , Plantas/genética , Flores/genética , Filogenia
15.
Medicine (Baltimore) ; 102(13): e33256, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37000112

RESUMEN

Elevated serum uric acid (SUA) levels are associated with coronary artery disease (CAD). However, whether this association is independent of traditional cardiovascular risk factors remains controversial. Our study aimed to determine the concentration of SUA in the presence and severity of CAD in multi-ethnic patients in Xinjiang, China. For this study, 412 consecutive patients with percutaneous coronary intervention (PCI) and 845 individuals with normal coronary angiograms were included in the study. CAD severity was evaluated using the Gensini score index. The SUA concentrations and the levels of various cardiometabolic risk factors were investigated. We assessed the relationship between SUA levels and other cardiometabolic risk factors. Logistic regression was used to evaluate risk factors for PCI patients. SUA levels were significantly elevated in PCI patients compared to those in control subjects (P < .01). With increased UA levels, we found that the risk factors for CAD increased. SUA concentration had a significant positive relationship with total cholesterol (P < .01), triglycerides (P < .01), low-density lipoprotein cholesterol (P < .01), and creatinine (P < .01) in both sexes. In the PCI group, there was no significant correlation between UA levels. SUA levels are not an independent risk factor for CAD. It can be concluded that in Xinjiang, China, SUA is related to multiple risk factors for CAD, but not related to the severity of CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Masculino , Femenino , Humanos , Enfermedad de la Arteria Coronaria/complicaciones , Ácido Úrico , Angiografía Coronaria , Estudios Retrospectivos , Estudios de Casos y Controles , Factores de Riesgo , LDL-Colesterol , China/epidemiología
16.
J Phys Chem Lett ; 14(8): 2223-2233, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36820508

RESUMEN

The fabrication of organic-inorganic perovskite field-effect transistors (FETs) with polymer gate dielectrics is challenging because of the solvent corrosion and wettability issues at interfaces. A few polymers have been integrated into perovskite transistors; however, these devices have high operating voltages due to low dielectric constants. Herein, poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) with a high dielectric constant is introduced into bottom-gate phenylethylammonium tin iodide perovskite [(PEA)2SnI4] FETs. Polytetrafluoroethylene (PTFE) and cross-linked poly(4-vinylphenol) (PVP) (CL-PVP) are used to address the issues of solvent corrosion and wettability. We design the PVDF-TrFE/PTFE and PVDF-TrFE/PTFE/CL-PVP dielectric layers, where the ferroelectric properties of PVDF-TrFE are reduced by PTFE. The (PEA)2SnI4 FETs operate at relatively low gate voltages, exhibiting good overall performance with average hole mobilities of 0.42 and 0.36 cm2 V-1 s-1. Our findings provide a feasible strategy for constructing low-operating-voltage perovskite FETs with large-dielectric-constant ferroelectric polymers as gate dielectrics by a solution processing technique.

17.
Eur J Pharmacol ; 938: 175420, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36427535

RESUMEN

Brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) pathway is a therapeutic target in cardiac diseases. A BDNF mimetic, 7,8-dihydroxyflavone (7,8-DHF), is emerging as a protective agent in cardiomyocytes; however, its potential role in cardiac fibroblasts (CFs) and fibrosis remains unknown. Thus, we aimed to explore the effects of 7,8-DHF on cardiac fibrosis and the possible mechanisms. Myocardial ischemia (MI) and transforming growth factor-ß1 (TGF-ß1) were used to establish models of cardiac fibrosis. Hematoxylin & eosin and Masson's trichrome stains were used for histological analysis and determination of collagen content in mouse myocardium. Cell viability kit, EdU (5-ethynyl-2'-deoxyuridine) assay and immunofluorescent stain were employed to examine the effects of 7,8-DHF on the proliferation and collagen production of CFs. The levels of collagen I, α-smooth muscle actin (α-SMA), TGF-ß1, Smad2/3, and Akt as well as circadian rhythm-related signals including brain and muscle Arnt-like protein 1 (Bmal1), period 2 (Per2), and cryptochrome 2 (Cry2) were analyzed. Treatment with 7,8-DHF markedly alleviated cardiac fibrosis in MI mice. It inhibited the activity of CFs accompanied by decreasing number of EdU-positive cells and downregulation of collagen I, α-SMA, TGF-ß1, and phosphorylation of Smad2/3. 7,8-DHF significantly restored the dysregulation of Bmal1, Per2, and Cry2, but inhibited the overactive Akt. Further, inhibition of Bmal1 by SR9009 effectively attenuated CFs proliferation and collagen production of CFs. In summary, these findings indicate that 7,8-DHF attenuates cardiac fibrosis and regulates circadian rhythmic signals, at least partly, by inhibiting Bmal1/Akt pathway, which may provide new insights into therapeutic cardiac remodeling.


Asunto(s)
Ritmo Circadiano , Flavonas , Miocardio , Animales , Ratones , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Fibroblastos , Fibrosis , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Flavonas/farmacología
18.
J Geriatr Cardiol ; 19(11): 853-866, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36561053

RESUMEN

BACKGROUND: Pathological cardiac hypertrophy is a compensated response to various stimuli and is considered a key risk factor for heart failure. 7,8-Dihydroxyflavone (7,8-DHF) is a flavonoid derivative that acts as a small-molecule brain-derived neurotrophic factor mimetic. The present study aimed to explore the potential role of 7,8-DHF in cardiac hypertrophy. METHODS: Kunming mice and H9c2 cells were exposed to transverse aortic constriction or isoproterenol (ISO) with or without 7,8-DHF, respectively. F-actin staining was performed to calculate the cell area. Transcriptional levels of hypertrophic markers, including ANP, BNP, and ß-MHC, were detected. Echocardiography, hematoxylin-eosin staining, and transmission electron microscopy were used to examine the cardiac function, histology, and ultrastructure of ventricles. Protein levels of mitochondria-related factors, such as adenosine monophosphate-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), were detected. RESULTS: 7,8-DHF inhibited compensated and decompensated cardiac hypertrophy, diminished the cross-sectional area, and alleviated the mitochondrial disorders of cardiomyocytes. Meanwhile, 7,8-DHF reduced the cell size and repressed the mRNA levels of the hypertrophic markers of ISO-treated cardiomyocytes. In addition, 7,8-DHF activated AMPK and PGC-1α signals without affecting the protein levels of mitochondrial dynamics-related molecules. The effects of 7,8-DHF were eliminanted by Compound C, an AMPK inhibitor. CONCLUSIONS: These findings suggest that 7,8-DHF inhibited cardiac hypertrophy and mitochondrial dysfunction by activating AMPK signaling, providing a potential agent for the treatment of pathological cardiac hypertrophy.

19.
Artículo en Inglés | MEDLINE | ID: mdl-36302180

RESUMEN

Two-dimensional (2D) layered organic-inorganic perovskites have great potential for fabricating field-effect transistors due to their unique structure that enables the horizontal transport of charge carriers in metal-halide octahedra, resembling the transport behavior in semiconducting channels. Their electronic band structures are mainly dominated by the metal-halide octahedra, which eventually determine the optical and electrical characteristics, whereas organic cations have no direct contributions but would impact the electronic structures via distorting the octahedra. So far, high performance has been achieved in 2D Sn perovskites compared to their Pb counterparts because the intrinsic differences of Sn promote transport properties. The champion hole mobility has been obtained in single-ring aromatic phenylethylammonium tin iodide perovskite [(PEA)2SnI4]. However, simple aliphatic monoammonium tin perovskites and their device applications have rarely been reported. Herein, 2D layered n-butylammonium tin iodide perovskite [(BA)2SnI4] thin films have been synthesized by a spin-coating approach. A structural phase transition occurs at about 225 K in the films, accompanied by the changes in the photoluminescence peak and exciton binding energy. Longitudinal optical (LO) phonons are found to govern the scattering of charge carriers and excitons via the Fröhlich interactions in the temperature range 77-300 K. The first-principles calculations predict that the perovskite has excellent transport characteristics comparable to those of molybdenum disulfide (MoS2) and methylammonium lead iodide perovskite (MAPbI3). The (BA)2SnI4 thin film field-effect transistors constructed on polymer dielectrics with a maximum hole mobility of 0.03 cm2 V-1 s-1 in ambient conditions have been successfully demonstrated for the first time. Our findings not only offer a deep insight into the physical properties of 2D layered aliphatic monoammonium tin perovskite thin films but also provide important experimental and theoretical guidance for their potential applications in lateral-type flexible optoelectronic devices.

20.
Sci Total Environ ; 851(Pt 1): 158210, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36028044

RESUMEN

Suspended particulate matter (SPM) concentration is an important biogeochemical parameter for water quality assessment and morphodynamic studies. In this study, the four recent SPM retrieval models developed for Bohai Sea were evaluated using in situ datasets, and the best performing model was selected to investigate the spatiotemporal dynamics of SPM in Bohai Sea from 2011 to 2021 based on 1164 satellite imageries. The results indicated that the satellite-derived SPM concentrations had a high accuracy (R2 = 0.86, relative percentage difference = 33.71 %). The SPM concentrations in the Bohai Sea demonstrated a significant decadal decreasing trend (0.503 mg/L/yr), and the distribution area with low SPM (<30 mg/L) increased by 3.29 % annually. The southern Bohai Sea declined observably, involving the Bohai Bay (2.07 mg/L/yr), Laizhou Bay (1.916 mg/L/yr), and central Bohai Sea (-0.661 mg/L/yr). Monthly SPM was characterized by significant seasonality. The SPM circulation pattern in the Bohai Strait was generally northerly inflow and southerly outflow. Significant wave heights (Hs) dominated the SPM variations and explained 58.9 % of monthly SPM changes in the Bohai Sea. The strong waves reduction was the main reason for the decadal decline of SPM concentrations. Wind waves associated with monsoons controlled seasonal variations of SPM and promoted the output in winter through the southern Bohai Strait. Storms could cause a sharp increase in SPM concentrations, especially in Bohai Bay and Laizhou Bay which were highly sensitive to northerly winds and strong waves. After the storm ended, the effects of short-duration storm might fade away within a few hours, while that of long-duration storm could last for 2-3 days. High sediment transport from Yellow River (>500 × 104 t/M) controlled 74.8 % of monthly SPM variations within 3-km area off the estuary, 45 % of that within 5-km area, and 28.4 % of that within 10-km area.


Asunto(s)
Material Particulado , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos/química , Material Particulado/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis
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