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1.
J Virol ; 97(6): e0043423, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37289052

RESUMO

Although influenza A viruses of several subtypes have occasionally infected humans, to date only those of the H1, H2, and H3 subtypes have led to pandemics and become established in humans. The detection of two human infections by avian H3N8 viruses in April and May of 2022 raised pandemic concerns. Recent studies have shown the H3N8 viruses were introduced into humans from poultry, although their genesis, prevalence, and transmissibility in mammals have not been fully elucidated. Findings generated from our systematic influenza surveillance showed that this H3N8 influenza virus was first detected in chickens in July 2021 and then disseminated and became established in chickens over wider regions of China. Phylogenetic analyses revealed that the H3 HA and N8 NA were derived from avian viruses prevalent in domestic ducks in the Guangxi-Guangdong region, while all internal genes were from enzootic poultry H9N2 viruses. The novel H3N8 viruses form independent lineages in the glycoprotein gene trees, but their internal genes are mixed with those of H9N2 viruses, indicating continuous gene exchange among these viruses. Experimental infection of ferrets with three chicken H3N8 viruses showed transmission through direct contact and inefficient transmission by airborne exposure. Examination of contemporary human sera detected only very limited antibody cross-reaction to these viruses. The continuing evolution of these viruses in poultry could pose an ongoing pandemic threat. IMPORTANCE A novel H3N8 virus with demonstrated zoonotic potential has emerged and disseminated in chickens in China. It was generated by reassortment between avian H3 and N8 virus(es) and long-term enzootic H9N2 viruses present in southern China. This H3N8 virus has maintained independent H3 and N8 gene lineages but continues to exchange internal genes with other H9N2 viruses to form novel variants. Our experimental studies showed that these H3N8 viruses were transmissible in ferrets, and serological data suggest that the human population lacks effective immunological protection against it. With its wide geographical distribution and continuing evolution in chickens, other spillovers to humans can be expected and might lead to more efficient transmission in humans.


Assuntos
Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Animais , Humanos , Influenza Humana/epidemiologia , Galinhas , Saúde Pública , Vírus da Influenza A Subtipo H9N2/genética , Filogenia , Furões , China/epidemiologia , Aves Domésticas
2.
J Acoust Soc Am ; 155(4): 2517-2537, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38591940

RESUMO

The shear stress transport turbulence model is employed to conduct a detailed study of flow characteristics at the highest efficiency point and near-stall point in a full-channel 1.5-stage compressor in this paper. The simulation results for the compressor's total pressure ratio and efficiency exhibit good agreement with experimental data. Emphasis is placed on examining the internal flow structure in the tip area of the compressor rotor under near-stall conditions. The results reveal that significant differences in flow structure primarily occur in the tip area as the compressor approaches stall. Specifically, a reduction in turbulent kinetic energy is observed in a region spanning approximately 20%-60% of the chord length on the rotor suction face near-stall conditions. Two additional peak frequencies, at 0.8 and 1.6 times the blade passage frequency, are observed, and the intricate flow phenomena are elaborated at the near-stall point. The near-stall point exhibits greater noise levels than the highest efficiency point, where the intensity of the surface source increases by more than 10 dB, peaking at 20 dB. This additional peak serves as a significant supplementary noise source near the stall point, leading to a maximum increase of 33.3 dB in the free radiated sound power. The acoustic response within the duct indicates that the compressor operating at the near-stall point continues to produce substantial noise on the actual test bench, showing an average increase of 6 dB in noise levels, and the distribution of the additional peak single-tone noise at the entrance significantly differs from that observed at the highest efficiency point.

3.
Small ; : e2310199, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063859

RESUMO

Solution-processable near-infrared (NIR) photodetectors are urgently needed for a wide range of next-generation electronics, including sensors, optical communications and bioimaging. However, it is rare to find photodetectors with >300 kHz cut-off frequencies, especially in the NIR region, and many of the emerging inorganic materials explored are comprised of toxic elements, such as lead. Herein, solution-processed AgBiS2 photodetectors with high cut-off frequencies under both white light (>1 MHz) and NIR (approaching 500 kHz) illumination are developed. These high cut-off frequencies are due to the short transit distances of charge-carriers in the ultrathin photoactive layer of AgBiS2 photodetectors, which arise from the strong light absorption of this material, such that film thicknesses well below 120 nm are sufficient to absorb >65% of NIR to visible light. It is also revealed that ion migration plays a critical role in the photo-response speed of these devices, and its detrimental effects can be mitigated by finely tuning the thickness of the photoactive layer, which is important for achieving low dark current densities as well. These outstanding characteristics enable the realization of air-stable, real-time heartbeat sensors based on NIR AgBiS2 photodetectors, which strongly motivates their future integration in high-throughput systems.

4.
J Gastroenterol Hepatol ; 38(2): 290-300, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36342849

RESUMO

BACKGROUND AND AIM: Aberrant DNA methylation has been found in various cancer types including gastric cancer, yet the genome-wide DNA methylation profile of gastric cardia cancer (GCC) remains unclear. Therefore, we aimed to profile the DNA methylation pattern of GCC and identify promising diagnostic epigenetic biomarkers. METHODS: We investigated the genome-wide DNA methylation pattern in eight pairs of GCC and adjacent normal tissues using Illumina 850K microarrays. Subsequently, bisulfite-pyrosequencing and quantitative real-time PCR were performed on eight pairs of GCC-adjacent normal tissues for validation. Finally, we performed immunohistochemistry to examine ADHFE1 expression on 126 pairs of GCC-adjacent normal samples. RESULTS: DNA methylome analysis showed global hypomethylation and local hypermethylation of promoter cytosine-phosphate-guanine (CpG) islands (CGIs) in GCC tissues compared with gastric cardia normal mucosa (P < 2.2 × 10-16 ). Differential methylation analysis identified a total of 91 723 differentially-methylated probes (DMPs), and the candidate gene with the largest average DNA methylation difference mapped to ADHFE1 (mean Δß = 0.53). Subsequently, three DMPs in the ADHFE1 promoter were validated by pyrosequencing. Notably, the mean methylation level of the three candidate DMPs (ADHFE1_cg08090772, ADHFE1_cg19283840, and ADHFE1_cg20295442) was negatively associated with ADHFE1 mRNA expression level (Spearman rho = -0.64, P = 0.01). Moreover, both mRNA (P = 0.0213) and protein (P < 0.0001) expression of ADHFE1 were significantly decreased in GCCs compared with the adjacent normal tissues. CONCLUSIONS: Our results reveal DNA methylation aberrations in GCC and that ADHFE1 gene DNA methylation contributes to the risk of GCC, thus providing novel mechanistic insights into gastric cardia cancer carcinogenesis.


Assuntos
Metilação de DNA , Neoplasias Gástricas , Humanos , Cárdia , RNA Mensageiro , Ilhas de CpG , Regulação Neoplásica da Expressão Gênica
5.
Environ Res ; 216(Pt 4): 114779, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370816

RESUMO

Evidence indicates that individual or groups of polybrominated diphenyl ethers (PBDEs) are associated with risk of breast cancer (BC). Epidemiological studies of PBDEs and BC progression are scarce. This study aimed to investigate the relationships between PBDE burdens in adipose tissues and prognostic biomarkers of BC as well as progression-free survival (PFS) of patients for the first time. The concentrations of 14 PBDE congeners in breast adipose tissues of 183 cases from the eastern area of southern China were analyzed by gas chromatography-mass spectrometry (GC-MS). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression models for the associations between PBDE levels and prognostic biomarkers. Kaplan-Meier and Cox regression analyses were conducted to identify the correlations between PBDEs and PFS. The results showed that BDE-99 and 190 levels were positively associated with clinical stage and N stage respectively (OR = 2.61 [1.26-5.40], OR = 2.78 [1.04-7.46]). Concentrations of BDE-28 and BDE-183 were negatively associated with the expression of estrogen receptor (ER) (OR = 0.30 [0.11-0.81]; 0.39 [0.15-0.99]) and progesterone receptor (PR) (OR = 0.36 [0.14-0.92]; 0.37 [0.15-0.91]), and increased BDE-47 was associated with lower human epidermal growth factor receptor 2 (HER2) expression (OR = 0.44 [0.23-0.86]). Adipose levels of BDE-71, 99, 138, 153, 154 and total PBDEs were positively associated with p53 expression (all P < 0.05). Finally, BDE-47, 99 and 183 were considered as independent prognostic factors for shorter PFS in the Cox models (adjusted hazard ratios = 3.14 [1.26-7.82]; 2.25 [1.03-4.94]; 2.60 [1.08-6.25], respectively). The recurrence risk and prognosis of BC may be closely bound to the body burdens of certain PBDE congeners. Further epidemiological and experimental studies are needed for confirmation.


Assuntos
Neoplasias da Mama , Éteres Difenil Halogenados , Humanos , Feminino , Éteres Difenil Halogenados/análise , Neoplasias da Mama/epidemiologia , Intervalo Livre de Progressão , Prognóstico , Tecido Adiposo/química , China/epidemiologia , Hospitais , Biomarcadores
6.
J Am Chem Soc ; 144(27): 12102-12115, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35759794

RESUMO

Colloidal lead-halide perovskite nanocrystals (LHP NCs) have emerged over the past decade as leading candidates for efficient next-generation optoelectronic devices, but their properties and performance critically depend on how they are purified. While antisolvents are widely used for purification, a detailed understanding of how the polarity of the antisolvent influences the surface chemistry and composition of the NCs is missing in the field. Here, we fill this knowledge gap by studying the surface chemistry of purified CsPbBrxI3-x NCs as the model system, which in itself is considered a promising candidate for pure-red light-emitting diodes and top-cells for tandem photovoltaics. Interestingly, we find that as the polarity of the antisolvent increases (from methyl acetate to acetone to butanol), there is a blueshift in the photoluminescence (PL) peak of the NCs along with a decrease in PL quantum yield (PLQY). Through transmission electron microscopy and X-ray photoemission spectroscopy measurements, we find that these changes in PL properties arise from antisolvent-induced iodide removal, which leads to a change in halide composition and, thus, the bandgap. Using detailed nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) measurements along with density functional theory calculations, we propose that more polar antisolvents favor the detachment of the oleic acid and oleylamine ligands, which undergo amide condensation reactions, leading to the removal of iodide anions from the NC surface bound to these ligands. This work shows that careful selection of low-polarity antisolvents is a critical part of designing the synthesis of NCs to achieve high PLQYs with minimal defect-mediated phase segregation.

7.
Cell Commun Signal ; 20(1): 30, 2022 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-35279183

RESUMO

BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) represents an efficient therapeutic method for atherosclerosis but conveys a risk of causing restenosis. Endothelial colony-forming cell-derived exosomes (ECFC-exosomes) are important mediators during vascular repair. This study aimed to investigate the therapeutic effects of ECFC-exosomes in a rat model of atherosclerosis and to explore the molecular mechanisms underlying the ECFC-exosome-mediated effects on ox-LDL-induced endothelial injury. METHODS: The effect of ECFC-exosome-mediated autophagy on ox-LDL-induced human microvascular endothelial cell (HMEC) injury was examined by cell counting kit-8 assay, scratch wound assay, tube formation assay, western blot and the Ad-mCherry-GFP-LC3B system. RNA-sequencing assays, bioinformatic analysis and dual-luciferase reporter assays were performed to confirm the interaction between the miR-21-5p abundance of ECFC-exosomes and SIPA1L2 in HMECs. The role and underlying mechanism of ECFC-exosomes in endothelial repair were explored using a high-fat diet combined with balloon injury to establish an atherosclerotic rat model of vascular injury. Evans blue staining, haematoxylin and eosin staining and western blotting were used to evaluate vascular injury. RESULTS: ECFC-exosomes were incorporated into HMECs and promoted HMEC proliferation, migration and tube formation by repairing autophagic flux and enhancing autophagic activity. Subsequently, we demonstrated that miR-21-5p, which is abundant in ECFC-exosomes, binds to the 3' untranslated region of SIPA1L2 to inhibit its expression, and knockout of miR-21-5p in ECFC-exosomes reversed ECFC-exosome-decreased SIPA1L2 expression in ox-LDL-induced HMEC injury. Knockdown of SIPA1L2 repaired autophagic flux and enhanced autophagic activity to promote cell proliferation in ox-LDL-treated HMECs. ECFC-exosome treatment attenuated vascular endothelial injury, regulated lipid balance and activated autophagy in an atherogenic rat model of vascular injury, whereas these effects were eliminated with ECFC-exosomes with knockdown of miR-21-5p. CONCLUSIONS: Our study demonstrated that ECFC-exosomes protect against atherosclerosis- or PTCA-induced vascular injury by rescuing autophagic flux and inhibiting SIAP1L2 expression through delivery of miR-21-5p. Video Abstract.


Assuntos
Aterosclerose , Exossomos , MicroRNAs , Lesões do Sistema Vascular , Animais , Apoptose , Aterosclerose/metabolismo , Autofagia , Células Cultivadas , Células Endoteliais/metabolismo , Exossomos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Lesões do Sistema Vascular/metabolismo
8.
Am J Physiol Heart Circ Physiol ; 320(2): H867-H880, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356961

RESUMO

Dysfunction of late endothelial progenitor cells (EPCs) has been suggested to be associated with hypertension. ß2-Adrenergic receptor (ß2AR) is a novel and key target for EPC homing. Here, we proposed that attenuated ß2AR signaling contributes to EPCs dysfunction, whereas enhanced ß2AR signaling restores EPCs' functions in hypertension. EPCs derived from hypertensive patients exhibited reduced cell number, impaired in vitro migratory and adhesion abilities, and impaired re-endothelialization after transplantation in nude mice with carotid artery injury. ß2AR expression of EPCs from hypertensive patients was markedly downregulated, whereas the phosphorylation of the p38 mitogen-activated protein kinase (p38-MAPK) was elevated. The cleaved caspase-3 levels were elevated in EPCs. The overexpression of ß2AR in EPCs from hypertensive patients inhibited p38-MAPK signaling, whereas it enhanced in vitro EPC proliferation, migration, and adhesion and in vivo re-endothelialization. The ß2AR-mediated effects were attenuated by treating the EPCs with a neutralizing monoclonal antibody against ß2AR, which could be partially antagonized by the p38-MAPK inhibitor SB203580. Moreover, shear stress stimulation, a classic nonpharmacological intervention, increased the phosphorylation levels of ß2AR and enhanced the in vitro and in vivo functions of EPCs from hypertensive patients. Collectively, the current investigation demonstrated that impaired ß2AR/p38-MAPK/caspase-3 signaling at least partially reduced the re-endothelialization capacity of EPCs from hypertensive patients. Restoration of ß2AR expression and shear stress treatment could improve their endothelial repair capacity by regulating the p38-MAPK/caspase-3 signaling pathway. The clinical significance of ß2AR in endothelium repair still requires further investigation.NEW & NOTEWORTHY Impaired ß2-adrenergic receptor (ß2AR) expression with an elevation of p38-MAPK/caspase-3 signaling at least partially contributes to the decline of re-endothelialization capacity of late endothelial progenitor cells (EPCs) from hypertensive patients. ß2AR gene transfer and shear stress treatment improve the late EPC-mediated enhancement of the re-endothelialization capacity in hypertensive patients through activating ß2AR/p38-MAPK/caspase-3 signaling. The present study is the first to reveal the potential molecular mechanism of the impaired endothelium-reparative capacity of late EPCs in hypertension after vascular injury and strongly suggests that ß2AR is a novel and crucial therapeutic target for increasing EPC-mediated re-endothelialization capacity in hypertension.


Assuntos
Lesões das Artérias Carótidas/prevenção & controle , Proliferação de Células , Células Progenitoras Endoteliais/metabolismo , Hipertensão/metabolismo , Reepitelização , Receptores Adrenérgicos beta 2/metabolismo , Animais , Apoptose , Lesões das Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/patologia , Estudos de Casos e Controles , Caspase 3/metabolismo , Adesão Celular , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Células Progenitoras Endoteliais/patologia , Células Progenitoras Endoteliais/transplante , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipertensão/patologia , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
J Recept Signal Transduct Res ; 41(1): 6-14, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32605511

RESUMO

Acute myocardial infarction (AMI) represents a severe coronary heart disease with relatively high rate of mortality and usually can lead to the damage of the myocardial tissues. Reperfusion of the ischemic myocardial tissues can minimize AMI-induced damage. As far as we know, the molecular mechanisms underlying ischemia/reperfusion (I/R)-induced injury remains elusive. This study was undertaken to explore the role of miR-1247-3p in regulating myocardial I/R injury. The hypoxia/reoxygenation (H/R)-treated H9c2 cells showed a decreased cell viability and mitochondrial membrane potential with an increase in the apoptosis; furthermore, miR-1247-3p was down-regulated in these cells. MiR-1247-3p overexpression attenuated H/R-induced H9c2 cell injury; while miR-1247-3p knockdown in H9c2 cells exhibited similar effects being observed in H/R-treated cells. The bioinformatics prediction revealed Bcl-2-like protein 11 (BCL2L11) and caspase-2 were two potential targets for miR-1247-3p, and functional assays confirmed that miR-1247-3p targeted both BCL2L11 and caspase-2 3' untranslated regions, which lead to the repressed expression of these genes. Silencing of BCL2L11 and caspase-2 both, respectively, counteracted the H9c2 cell injury caused by H/R treatment. Moreover, BCL2L11 and caspase-2 overexpression, respectively, impaired the protective effects of miR-1247-3p overexpression on H/R-treated H9c2 cells. The data in the present investigation revealed that miR-1247-3p restoration exhibited protective effects on H/R-induced cardiomyocyte injury through targeting BCL2L11 and caspase-2, implying that miR-1247-3p along with caspase-2/BCL2L11 signaling may provide novel sight for a better understating of I/R-induced myocardial damage. The role of miR-1247-3p might be further confirmed in animal models and clinical studies.


Assuntos
Proteína 11 Semelhante a Bcl-2/genética , Caspase 2/genética , MicroRNAs/genética , Miocárdio/metabolismo , Traumatismo por Reperfusão/genética , Animais , Apoptose/genética , Hipóxia Celular/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica/genética , Humanos , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Substâncias Protetoras/farmacologia , Ratos , Traumatismo por Reperfusão/patologia , Transdução de Sinais/genética
10.
Nanotechnology ; 32(13): 132004, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33260167

RESUMO

Lead-halide perovskites have demonstrated astonishing increases in power conversion efficiency in photovoltaics over the last decade. The most efficient perovskite devices now outperform industry-standard multi-crystalline silicon solar cells, despite the fact that perovskites are typically grown at low temperature using simple solution-based methods. However, the toxicity of lead and its ready solubility in water are concerns for widespread implementation. These challenges, alongside the many successes of the perovskites, have motivated significant efforts across multiple disciplines to find lead-free and stable alternatives which could mimic the ability of the perovskites to achieve high performance with low temperature, facile fabrication methods. This Review discusses the computational and experimental approaches that have been taken to discover lead-free perovskite-inspired materials, and the recent successes and challenges in synthesizing these compounds. The atomistic origins of the extraordinary performance exhibited by lead-halide perovskites in photovoltaic devices is discussed, alongside the key challenges in engineering such high-performance in alternative, next-generation materials. Beyond photovoltaics, this Review discusses the impact perovskite-inspired materials have had in spurring efforts to apply new materials in other optoelectronic applications, namely light-emitting diodes, photocatalysts, radiation detectors, thin film transistors and memristors. Finally, the prospects and key challenges faced by the field in advancing the development of perovskite-inspired materials towards realization in commercial devices is discussed.

12.
Nanoscale ; 16(21): 10155-10167, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38715539

RESUMO

Chalcogenide solar absorbers, such as AgBiS2 and kesterites, have gained a resurgence of interest recently, owing to their high stability compared to metal-halide compounds, as well as their rising efficiencies in photovoltaic devices. Although their optical and electronic properties are conventionally tuned through the composition and structure, cation disorder has increased in prominence as another important parameter that influences these properties. In this minireview, we define cation disorder as the occupation of a cation crystallographic site with different species, and the homogeneity of this cation disorder as how regular the alternation of species in this site is. We show that cation disorder is not necessarily detrimental, and can lead to increases in absorption coefficient and reductions in bandgap, enabling the development of ultrathin solar absorbers for lightweight photovoltaics. Focusing on kesterites and ABZ2 materials (where A = monovalent cation, B = divalent cation, and Z is a chalcogenide anion), we discuss how the degree and homogeneity of cation disorder influences the optical properties, charge-carrier transport and photovoltaic performance of these materials, as well as how cation disorder could be tuned and quantified. We finish with our perspectives on the important questions moving forward in making use of cation disorder engineering as a route to achieve more efficient solar absorbers.

13.
Adv Mater ; 36(1): e2305841, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37947249

RESUMO

Sb2 S3 is a promising environmentally friendly semiconductor for high performance solar cells. But, like many other polycrystalline materials, Sb2 S3 is limited by nonradiative recombination and carrier scattering by grain boundaries (GBs). This work shows how the GB density in Sb2 S3 films can be significantly reduced from 1068 ± 40 to 327 ± 23 nm µm-2 by incorporating an appropriate amount of Ce3+ into the precursor solution for Sb2 S3 deposition. Through extensive characterization of structural, morphological, and optoelectronic properties, complemented with computations, it is revealed that a critical factor is the formation of an ultrathin Ce2 S3 layer at the CdS/Sb2 S3 interface, which can reduce the interfacial energy and increase the adhesion work between Sb2 S3 and the substrate to encourage heterogeneous nucleation of Sb2 S3 , as well as promote lateral grain growth. Through reductions in nonradiative recombination at GBs and/or the CdS/Sb2 S3 heterointerface, as well as improved charge-carrier transport properties at the heterojunction, this work achieves high performance Sb2 S3 solar cells with a power conversion efficiency reaching 7.66%. An impressive open-circuit voltage (VOC ) of 796 mV is achieved, which is the highest reported thus far for Sb2 S3 solar cells. This work provides a strategy to simultaneously regulate the nucleation and growth of Sb2 S3 absorber films for enhanced device performance.

14.
Nat Commun ; 15(1): 316, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182589

RESUMO

The knowledge of minority and majority charge carrier properties enables controlling the performance of solar cells, transistors, detectors, sensors, and LEDs. Here, we developed the constant light induced magneto transport method which resolves electron and hole mobility, lifetime, diffusion coefficient and length, and quasi-Fermi level splitting. We demonstrate the implication of the constant light induced magneto transport for silicon and metal halide perovskite films. We resolve the transport properties of electrons and holes predicting the material's effectiveness for solar cell application without making the full device. The accessibility of fourteen material parameters paves the way for in-depth exploration of causal mechanisms limiting the efficiency and functionality of material structures. To demonstrate broad applicability, we further characterized twelve materials with drift mobilities spanning from 10-3 to 103 cm2V-1s-1 and lifetimes varying between 10-9 and 10-3 seconds. The universality of our method its potential to advance optoelectronic devices in various technological fields.

15.
NPJ Biofilms Microbiomes ; 10(1): 25, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509085

RESUMO

Hyperuricemia (HUA) is a metabolic syndrome caused by abnormal purine metabolism. Although recent studies have noted a relationship between the gut microbiota and gout, whether the microbiota could ameliorate HUA-associated systemic purine metabolism remains unclear. In this study, we constructed a novel model of HUA in geese and investigated the mechanism by which Lactobacillus rhamnosus GG (LGG) could have beneficial effects on HUA. The administration of antibiotics and fecal microbiota transplantation (FMT) experiments were used in this HUA goose model. The effects of LGG and its metabolites on HUA were evaluated in vivo and in vitro. Heterogeneous expression and gene knockout of LGG revealed the mechanism of LGG. Multi-omics analysis revealed that the Lactobacillus genus is associated with changes in purine metabolism in HUA. This study showed that LGG and its metabolites could alleviate HUA through the gut-liver-kidney axis. Whole-genome analysis, heterogeneous expression, and gene knockout of LGG enzymes ABC-type multidrug transport system (ABCT), inosine-uridine nucleoside N-ribohydrolase (iunH), and xanthine permease (pbuX) demonstrated the function of nucleoside degradation in LGG. Multi-omics and a correlation analysis in HUA patients and this goose model revealed that a serum proline deficiency, as well as changes in Collinsella and Lactobacillus, may be associated with the occurrence of HUA. Our findings demonstrated the potential of a goose model of diet-induced HUA, and LGG and proline could be promising therapies for HUA.


Assuntos
Hiperuricemia , Lacticaseibacillus rhamnosus , Humanos , Hiperuricemia/terapia , Nucleosídeos , Lactobacillus , Prolina , Purinas
16.
J Transl Med ; 11: 245, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24090193

RESUMO

BACKGROUND: Protein Tyrosine Phosphatase Receptor-type O (PTPRO) has recently been in the spotlight as a tumor suppressor, whose encoding gene is frequently methylated in cancers. We examined the methylation status of the PTPRO gene promoter in breast cancer and evaluated the correlation between PTPRO promoter methylation and both clinicopathological parameters and prognosis of breast cancer patients. METHODS: Two hundred twenty-one formalin-fixed, paraffin-embedded (FFPE) tumor tissues, 20 FFPE normal adjacent tissues and 24 matched plasma samples, collected from primary breast cancer patients, were assessed for PTPRO gene promoter methylation using methylation-specific PCR. Associations of promoter methylation with clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect on survival. RESULTS: 175 samples gave identifiable PCR products, of which 130 cases (74.3%) had PTPRO gene promoter methylation. PTPRO methylation correlated with higher histological grade (P = 0.028), but not other clinical parameters. Multivariate analysis indicated that overall survival (OS) was significantly poorer in HER2-positive, but not ER-positive patients with methylated-PTPRO. Methylated-PTPRO was detectable in matched plasma samples and only observed in plasma from patients whose corresponding primary tumors were also methylated. CONCLUSIONS: PTPRO methylation is a common event in the primary breast cancer and can be reliably detected in peripheral blood samples. PTPRO methylation is associated with poor survival only in HER2-positive patients, suggesting use of PTPRO methylation as a prognostic factor for breast cancer and for optimizing individualized therapy for HER2-positive patients.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Metilação de DNA/genética , Medicina de Precisão , Regiões Promotoras Genéticas , Receptor ErbB-2/metabolismo , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Inclusão em Parafina , Prognóstico , Modelos de Riscos Proporcionais , Fixação de Tecidos , Resultado do Tratamento , Adulto Jovem
17.
Cancer Lett ; 567: 216283, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37331584

RESUMO

Protein tyrosine phosphatase receptor-type O (PTPRO) is a membrane-bound tyrosine phosphatase. Notably, epigenetically silenced PTPRO due to promoter hypermethylation is frequently linked to malignancies. In this study, we used cellular and animal models, and patient samples to demonstrate that PTPRO can suppress the metastasis of esophageal squamous cell carcinoma (ESCC). Mechanistically, PTPRO can inhibit MET-mediated metastasis by dephosphorylating Y1234/1235 in the kinase activation loop of MET. Patients with PTPROlow/p-METhigh had significantly poor prognosis, suggesting that PTPROlow/p-METhigh can serve as an independent prognostic factor for patients with ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Metástase Linfática , Linhagem Celular Tumoral , Monoéster Fosfórico Hidrolases , Prognóstico
18.
J Acoust Soc Am ; 132(1): 452-64, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22779492

RESUMO

This paper addresses the problem of noise reduction in the time domain where the clean speech sample at every time instant is estimated by filtering a vector of the noisy speech signal. Such a clean speech estimate consists of both the filtered speech and residual noise (filtered noise) as the noisy vector is the sum of the clean speech and noise vectors. Traditionally, the filtered speech is treated as the desired signal after noise reduction. This paper proposes to decompose the clean speech vector into two orthogonal components: one is correlated and the other is uncorrelated with the current clean speech sample. While the correlated component helps estimate the clean speech, it is shown that the uncorrelated component interferes with the estimation, just as the additive noise. Based on this orthogonal decomposition, the paper presents a way to define the error signal and cost functions and addresses the issue of how to design different optimal noise reduction filters by optimizing these cost functions. Specifically, it discusses how to design the maximum SNR filter, the Wiener filter, the minimum variance distortionless response (MVDR) filter, the tradeoff filter, and the linearly constrained minimum variance (LCMV) filter. It demonstrates that the maximum SNR, Wiener, MVDR, and tradeoff filters are identical up to a scaling factor. It also shows from the orthogonal decomposition that many performance measures can be defined, which seem to be more appropriate than the traditional ones for the evaluation of the noise reduction filters.


Assuntos
Ruído , Fala/fisiologia , Humanos , Matemática , Mascaramento Perceptivo/fisiologia , Razão Sinal-Ruído , Fatores de Tempo
19.
Cytotechnology ; 74(2): 231-243, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35464163

RESUMO

Nasopharyngeal carcinoma (NPC) is a malignant tumor with a poor prognosis. Studies have shown that esophageal carcinoma related gene 4 (ECRG4) is hypermethylated and significantly downregulated in NPC tissues. However, the role of ECRG4 in NPC, and in particular the underlying molecular mechanism, is largely unclear. In this study, using immunohistochemical staining of ECRG4 in NPC and normal specimens, we confirmed that ECRG4 was downregulated in human NPC tissues. In addition, various biological and molecular studies were carried out and the results showed that ECRG4 exerted anticancer effect in NPC, including inhibiting cell growth, migration, and invasion of NPC cells in vitro. Moreover, restoring ECRG4 expression suppressed the in vivo tumorigenesis of CNE2 cells. ECRG4 inhibited AKT/GSK3ß/ß-catenin signaling, as well as the downstream targets of ß-catenin. LiCl treatment, which reduced GSK3ß phosphorylation and upregulated ß-catenin expression, restored the invasive ability of ECRG4-overexpressing NPC cells. Furthermore, we showed that the DNA methylation inhibitor 5-aza-dC reduced ECRG4 methylation and the invasive ability of negative control cells, but not that of ECRG4-overexpressing cells, suggesting that the inhibitory effect of 5-aza-dC depends on low expression of ECRG4. Collectively, our results demonstrated that ECRG4 downregulation contributed to NPC growth and invasion by activating AKT/GSK3ß/ß-catenin signaling pathway. ECRG4 could be a promising therapeutic target for the treatment of NPC. Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-022-00520-8.

20.
Front Cell Dev Biol ; 10: 792933, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252173

RESUMO

Cadmium (Cd) exposure has been implicated in the etiology of esophageal squamous cell carcinoma (ESCC), albeit with inconsistent results from epidemiologic studies and without causal evidence. In this study, we explore the relationship of Cd exposure and the development, progression and therapeutic resistance of ESCC. A total of 150 ESCC patients and 177 matched controls from a coastal region with a high incidence of ESCC in China were included in the study. It was found that the median blood Cd level (BCL) was significantly higher in ESCC patients than that in the controls. Odds ratios for ESCC risk were 3.12 (95% CI 1.54-6.30) and 3.71 (95% CI 1.84-7.48) in the third and fourth quartiles of Cd distribution, respectively. Notably, BCL above 4.71 µg/L was strongly associated with shorter progression-free survival time compared to that below 1.60 µg/L (p < 0.001). The chronic Cd-treated ESCC cells (CCT-ESCC) CCT-EC109 and CCT-EC9706 exhibited increased cell proliferation and tumorigenesis, enhanced migration and invasion, and upregulated EMT biomarkers following 12 weeks of exposure to 5 µM cadmium chloride. Furthermore, Cd treatment attenuated the efficacy of 5-fluorouracil, cisplatin and irradiation treatment in CCT-ESCC cells both in vitro and in vivo. Moreover, we revealed that Cd stimulated the cancer cell stemness and Wnt/ß-catenin signaling pathway in the CCT-ESCC cells. Additionally, 5-aza-2-deoxy-cytidine treatment resulted in suppression of the Wnt/ß-catenin signaling pathway and rescue of the Cd-induced cell radioresistance. These results offer new insights into the role of environmental Cd exposure in the development, progression and chemoradioresistance of ESCC.

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