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1.
Mol Cancer ; 21(1): 12, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986849

RESUMEN

BACKGROUND: More and more studies have shown that circular RNAs (circRNAs) play a critical regulatory role in many cancers. However, the potential molecular mechanism of circRNAs in prostate cancer (PCa) remains largely unknown. METHODS: Differentially expressed circRNAs were identified by RNA sequencing. The expression of hsa_circ_0003258 was evaluated using quantitative real-time PCR and RNA in situ hybridization. The impacts of hsa_circ_0003258 on the metastasis of PCa cells were investigated by a series of in vitro and in vivo assays. Lastly, the underlying mechanism of hsa_circ_0003258 was revealed by Western blot, biotin-labeled RNA pulldown, RNA immunoprecipitation, luciferase assays and rescue experiments. RESULTS: Increased expression of hsa_circ_0003258 was found in PCa tissues and was associated with advanced TNM stage and ISUP grade. Overexpression of hsa_circ_0003258 promoted PCa cell migration by inducing epithelial mesenchymal transformation (EMT) in vitro as well as tumor metastasis in vivo, while knockdown of hsa_circ_0003258 exerts the opposite effect. Mechanistically, hsa_circ_0003258 could elevate the expression of Rho GTPase activating protein 5 (ARHGAP5) via sponging miR-653-5p. In addition, hsa_circ_0003258 physically binds to insulin like growth factor 2 mRNA binding protein 3 (IGF2BP3) in the cytoplasm and enhanced HDAC4 mRNA stability, in which it activates ERK signalling pathway, then triggers EMT programming and finally accelerates the metastasis of PCa. CONCLUSIONS: Upregulation of hsa_circ_0003258 drives tumor progression through both hsa_circ_0003258/miR-653-5p/ARHGAP5 axis and hsa_circ_0003258/IGF2BP3 /HDAC4 axis. Hsa_circ_0003258 may act as a promising biomarker for metastasis of PCa and an attractive target for PCa intervention.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias de la Próstata/genética , Interferencia de ARN , ARN Circular/genética , Proteínas de Unión al ARN/genética , Anciano , Anciano de 80 o más Años , Animales , Estudios de Casos y Controles , Línea Celular Tumoral , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Estabilidad del ARN , Proteínas de Unión al ARN/metabolismo
2.
Phys Rev Lett ; 127(21): 214301, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34860093

RESUMEN

The interplay between real-space topological lattice defects and the reciprocal-space topology of energy bands can give rise to novel phenomena, such as one-dimensional topological modes bound to screw dislocations in three-dimensional topological insulators. We obtain direct experimental observations of dislocation-induced helical modes in an acoustic analog of a weak three-dimensional topological insulator. The spatial distribution of the helical modes is found through spin-resolved field mapping, and verified numerically by tight-binding and finite-element calculations. These one-dimensional helical channels can serve as robust waveguides in three-dimensional media. Our experiment paves the way to studying novel physical modes and functionalities enabled by topological lattice defects in three-dimensional classical topological materials.

3.
Chemistry ; 21(21): 7914-26, 2015 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-25877804

RESUMEN

Three unusual three-dimensional (3D) tetrazine chromophore-based metal-organic frameworks (MOFs) {(Et4 N)[WS4 Cu3 (CN)2 (4,4'-pytz)0.5 ]}n (1), {[MoS4 Cu4 (CN)2 (4,4'-pytz)2 ]⋅CH2 Cl2 }n (2), and {[WS4 Cu3 (4,4'-pytz)3 ]⋅[N(CN)2 ]}n (3; 4,4'-pytz=3,6-bis(4-pyridyl)tetrazine) have been synthesized and characterized by using FTIR and UV/Vis spectroscopy, elemental analysis, powder X-ray diffraction, gel permeation chromatography, steady-state fluorescence, and thermogravimetric analysis; their identities were confirmed by single-crystal X-ray diffraction studies. MOF 1 possesses the first five-connected M/S/Cu (M=Mo, W) framework with an unusual 3D (4(4) ⋅6(6) ) topology constructed from T-shaped [WS4 Cu3 ](+) clusters as nodes and single CN(-) /4,4'-pytz bridges as linkers. MOF 2 features a novel 3D MOF structure with (4(20) ⋅6(8) ) topology, in which the bridging 4,4'-pytz ligands exhibit unique distorted arch structures. MOF 3 displays the first 3D MOF structure based on flywheel-shaped [WS4 Cu3 ](+) clusters with a non-interpenetrating honeycomb-like framework and a heavily distorted "ACS" topology. Steady-state fluorescence studies of 1-3 reveal significant fluorescence emissions. The nonlinear optical (NLO) properties of 1-3 were investigated by using a Z-scan technique with 5 ns pulses at λ=532 nm. The Z-scan experimental results show that the π-delocalizable tetrazine-based 4,4'-pytz ligands contribute to the strong third-order NLO properties exhibited by 1-3. Time-dependent density functional theory studies afforded insight into the electronic transitions and spectral characterization of these functionalized NLO molecular materials.

4.
Ying Yong Sheng Tai Xue Bao ; 35(2): 489-500, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38523107

RESUMEN

The expansion of roads exacerbates the fragmentation of ecological networks and obstructs landscape connectivity. Scientific analysis of the impacts of different grades of roads on landscape connectivity and ecological networks is crucial for guiding road planning and ecological conservation. Based on the data of 2020 road network, land cover types, and digital elevation models, we used morphological spatial pattern analysis and circuit theory to construct ecological networks within different species dispersal distances (1, 3, 5, 10 km) in Fuzhou. We analyzed the impacts of roads of different grades (motorway, urban expressway, primary and secondary highway) on landscape connectivity at the landscape-patch-corridor scale. The results showed that at the landscape scale, overall landscape connectivity was significantly positively correlated with species dispersal distance. The motorway, urban expressway, primary and secondary highway had the lowest decline rate of overall landscape connectivity within a 10 km species dispersal range, being reduced by 15.6%, 5.3%, 1.5% and 5.2%, respectively. At the patch scale, in the comparison of roads of different grades, motorway led to the highest decline rate of patch connectivity within 1 and 5 km species dispersal range, while primary highway led to the highest decline rate of patch connectivity within 3 and 10 km species dispersal range. At the corridor scale, urban expressway led the highest increase rate of indices. The cost-weighted distance of the overall least-cost path, the ratio of cost-weighted distance to length, ove-rall effective resistance, and total corridor length within 5 km species dispersal range were increased by 43.4%, 33.2%, 57.3%, and 7.3%, respectively. As the distance of species dispersal increased, the patches with high importance were reduced from the northern, central, and northwestern regions to the northern regions, leading to a decrease in the living space of species, and the key corridors were gradually extending from the northwestern and southern regions to the central regions. Our results can guide the construction and optimization of Fuzhou's ecological network from an overall perspective, and provide a scientific basis for biodiversity conservation, ecological restoration, and road network planning under the context of limited land resource utilization.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Ciudades , Biodiversidad , China
5.
Nat Commun ; 15(1): 2332, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38485983

RESUMEN

As hypothetical topological defects in the geometry of spacetime, vortex strings could have played many roles in cosmology, and their distinct features can provide observable clues about the early universe's evolution. A key feature of vortex strings is that they can interact with Weyl fermionic modes and support massless chiral-anomaly states along strings. To date, despite many attempts to detect vortex strings in astrophysics or to emulate them in artificially created systems, observation of these vortex-string chiral modes remains experimentally elusive. Here we report experimental observations of vortex-string chiral modes using a metamaterial system. This is implemented by inhomogeneous perturbation of Yang-monopole phononic metamaterials. The measured linear dispersion and modal profiles confirm the existence of topological modes bound to and propagating along the string with the chiral anomaly. Our work provides a platform for studying diverse cosmic topological defects in astrophysics and offers applications as topological fibres in communication techniques.

6.
Nat Commun ; 15(1): 2174, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467627

RESUMEN

When electrons moving in two dimensions (2D) are subjected to a strong uniform magnetic field, they form flat bands called Landau levels (LLs). LLs can also arise from pseudomagnetic fields (PMFs) induced by lattice distortions. In three-dimensional (3D) systems, there has been no experimental demonstration of LLs  as a type of flat band thus far. Here, we report the experimental realization of a flat 3D LL in an acoustic crystal. Starting from a lattice whose bandstructure exhibits a nodal ring, we design an inhomogeneous distortion corresponding to a specific pseudomagnetic vector potential (PVP). This distortion causes the nodal ring states to break up into LLs, including a zeroth LL that is flat along all three directions. These findings suggest the possibility of using nodal ring materials to generate 3D flat bands, allowing access to strong interactions and other attractive physical regimes in 3D.

7.
Int J Cardiovasc Imaging ; 40(1): 27-34, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37843758

RESUMEN

This study was designed to retrospectively analyze the relationship between the levels of cardiac troponin T (cTnT) and cardiac troponin I (cTnI) and the development of left ventricular diastolic dysfunction (LVDD) in septic patients with diabetes mellitus. Furthermore, the predictive value of cTnT and cTnI in the LVDD development in those patients was investigated. The clinical information of 159 septic patients with diabetes mellitus treated in the intensive care unit of Affiliated Hospital of Chengde Medical University from June 2016 to January 2023 were retrospectively analyzed. These patients were separated into LVDD group (LVFP > 15 mmHg) and non-LVDD group (LVFP ≤ 15 mmHg) based on left ventricular filling pressure (LVFP). The differences in clinical data, echocardiographic parameters, as well as cTnT and cTnI levels between the LVDD and non-LVDD groups were compared. The relationship between the cTnT and cTnI levels and the echocardiographic parameters was studied using Pearson correlation analysis. Logistic regression analysis was conducted to explore the factors that influenced the LVDD development in septic patients with diabetes. Receiver operator characteristic (ROC) curves were created to evaluate the predictive value of cTnT and cTnI levels for the LVDD development in septic patients with diabetes. Totally 159 septic patients with diabetes were included in this study, with 97 patients in the LVDD group and 62 in the non-LVDD group. Compared with the non-LVDD group, patients in the LVDD group had much lower left ventricular (LV) early diastolic peak inflow velocity (E), LV advanced diastolic peak inflow velocity (A), E/A, and early diastolic mitral annular velocity (Em) while significantly higher E/Em. The LVDD group showed much higher levels of cTnI and cTnT than the non-LVDD group (P < 0.05). Significant positive correlation between log10cTnI level and E/Em ratio (r = 0.425, P < 0.001) was revealed by the Pearson correlation analysis. Multivariate analysis showed that E/A, E/Em, cTnI and cTnT were independent risk factors for the LVDD development in septic patients with diabetes (P < 0.05). As for ROC curve results, the area under the curve (AUC) of cTnT to predict the development of LVDD in septic patients with diabetes was 0.849 (95% CI 0.788-0.910, P < 0.001); the AUC of cTnI was 0.742 (95% CI 0.666-0.817, P < 0.001). Both cTnT and cTnI are independent risk factors and have predictive value for the LVDD development in septic patients with diabetes mellitus.


Asunto(s)
Diabetes Mellitus , Sepsis , Disfunción Ventricular Izquierda , Humanos , Estudios Retrospectivos , Valor Predictivo de las Pruebas , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Diabetes Mellitus/diagnóstico , Sepsis/complicaciones , Sepsis/diagnóstico , Troponina , Troponina T , Biomarcadores
8.
Arh Hig Rada Toksikol ; 75(1): 81-84, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38548379

RESUMEN

Organophosphorus poisoning is a critical condition that can cause central nervous system depression, respiratory failure, and death early on. As its clinical manifestations closely resemble those of carbamate pesticide poisoning, the aim of this case study is to present a case of misdiagnosis, initially identifying carbofuran poisoning as organophosphate in a patient suspect of a heatstroke. We also present a case of intentional self-poisoning with organophosphate dichlorvos to underline the likelihood of pesticide poisoning in patients exhibiting acute cholinergic symptoms when the ingested substance is not known. In such cases, empirical treatment with atropine and oxime can be started pending timely differential diagnosis to adjust treatment as necessary.


Asunto(s)
Insecticidas , Intoxicación por Organofosfatos , Plaguicidas , Intoxicación , Humanos , Carbamatos/uso terapéutico , Intoxicación por Organofosfatos/diagnóstico , Intoxicación por Organofosfatos/tratamiento farmacológico , Diclorvos/uso terapéutico , Intoxicación/terapia
9.
Aging (Albany NY) ; 16(2): 1581-1604, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38240702

RESUMEN

Basement membrane plays an important role in tumor invasion and metastasis, which is closely related to prognosis. However, the prognostic value and biology of basement membrane genes (BMGs) in prostate cancer (PCa) remain unknown. In the TCGA training set, we used differentially expressed gene analysis, protein-protein interaction networks, univariate and multivariate Cox regression, and least absolute shrinkage and selection operator regression to construct a basement membrane-related risk model (BMRM) and validated its effectiveness in the MSKCC validation set. Furthermore, the accurate nomogram was constructed to improve clinical applicability. Patients with PCa were divided into high-risk and low-risk groups according to the optimal cut-off value of the basement membrane-related risk score (BMRS). It was found that BMRS was significantly associated with RFS, T-stage, Gleason score, and tumor microenvironmental characteristics in PCa patients. Further analysis showed that the model grouping was closely related to tumor immune microenvironment characteristics, immune checkpoint inhibitors, and chemotherapeutic drug sensitivity. In this study, we developed a new BMGs-based prognostic model to determine the prognostic value of BMGs in PCa. Finally, we confirmed that THBS2, a key gene in BMRM, may be an important link in the occurrence and progression of PCa. This study provides a novel perspective to assess the prognosis of PCa patients and provides clues for the selection of future personalized treatment regimens.


Asunto(s)
Neoplasias de la Próstata , Microambiente Tumoral , Masculino , Humanos , Membrana Basal , Microambiente Tumoral/genética , Pronóstico , Neoplasias de la Próstata/genética , Nomogramas
10.
J Burn Care Res ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477626

RESUMEN

Hypertrophic scar development is a complication associated with wound healing, impacting local appearance and function. The type I/III collagen ratio affects the extent of hypertrophic scarring; a reduced ratio can ameliorate this. In this study, recombinant human collagen type III was developed. Liquid chromatography-tandem mass spectrometry was used to determine its amino acid sequence and confirm its high level of homology with natural human type III collagen. Recombinant human collagen type III displayed no cytotoxicity and did not confer skin irritation and sensitization. Immunofluorescence and western blot analyses of histidine following incubation with fibroblasts suggested cell entry of recombinant human collagen type III. Furthermore, recombinant human collagen type III promoted the synthesis of the natural type III collagen in fibroblasts, resulting in a more obvious increase of type III collagen content in fibroblasts than that of type I collagen, and then decreased the ratio of type I/III collagen. The results of 5-ethynyl-2'-deoxyuridine staining assay suggested enhanced fibroblast proliferation. Following local injection of recombinant human collagen type III, rabbit ear scarring was significantly reduced after 60 days. Vancouver Scar Scale evaluation showed that all index scores were significantly reduced. Western blotting and Picro-Sirius red staining showed that the natural type III collagen increase in scar tissue was greater than that of type I collagen, decreasing the type I/III ratio. In summary, recombinant human collagen type III can be taken up by fibroblasts and promote natural collagen synthesis-especially that of type III-thereby reducing the type I/III ratio and improving hypertrophic scarring.

11.
J Fungi (Basel) ; 9(3)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36983498

RESUMEN

The enoki mushroom (Flammulina filiformis) is one of the most important and popular edible mushrooms commercially in China. However, traditional mushroom cultivar identification is challenging due to poor accuracy, heavy workloads, and low reproducibility. To overcome this challenge, we developed a method for identifying F. filiformis strains using multiple nucleotide polymorphism sequencing (MNP-seq). This involved screening 179 universal MNP markers based on whole-genome sequencing data, constructing an MNP sequence library, and performing multiplex PCR amplification and high-sequencing. We further screened 69 core MNP markers and used them to build a neighbor-joining (NJ) phylogenetic tree of 232 cultivated and wild strains. Our analysis showed that all cultivars could be accurately separated by computing genetic similarity values and that the cultivars could be separated into 22 distinct evolutionary pedigrees. The specific value of genetic similarity can be used as the standard to distinguish F. filiformis cultivars, however, it needs to be comprehensively defined by the additional phenotype and biological characteristics of those strains in the future work.

12.
Adv Sci (Weinh) ; 10(36): e2303457, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37983567

RESUMEN

Gut microbiome is integral to the pathogenesis of ulcerative colitis. A novel probiotic Lactobacillus intestinalis (L. intestinalis) exerts a protective effect against dextran sodium sulfate-induced colitis in mice. Based on flow cytometry, colitis-associated Th17 cells are the target of L. intestinalis, which is supported by the lack of protective effects of L. intestinalis in T cell-null Rag1-/- mice or upon anti-IL-17-A antibody-treated mice. Although L. intestinalis exerts no direct effect on T cell differentiation, it decreases C/EBPA-driven gut epithelial SAA1 and SAA2 production, which in turn impairs Th17 cell differentiation. Cometabolism of L. intestinalis ALDH and host ALDH1A2 contributed to elevated biosynthesis of retinoic acid (RA), which accounts for the anti-colitis effect in RAR-α -mediated way. In a cohort of ulcerative colitis patients, it is observed that fecal abundance of L. intestinalis is negatively associated with the C/EBPA-SAA1/2-Th17 axis. Finally, L. intestinalis has a synergistic effect with mesalazine in alleviating murine colitis. In conclusion, L. intestinalis and associated metabolites, RA, have potential therapeutic effects for suppressing colonic inflammation by modulating the crosstalk between intestinal epithelia and immunity.


Asunto(s)
Colitis Ulcerosa , Colitis , Humanos , Animales , Ratones , Colitis Ulcerosa/tratamiento farmacológico , Células Th17/metabolismo , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Células Epiteliales/metabolismo , Tretinoina/metabolismo , Tretinoina/farmacología , Tretinoina/uso terapéutico
13.
Biomed Res Int ; 2022: 3092063, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35769676

RESUMEN

Long noncoding RNA (lncRNA) HLA complex P5 (HCP5) is correlated with multiple diseases, especially cancers. However, it remains to be further studied whether HCP5 is involved in the malignant behaviors of gliomas. This study is aimed at investigating the role and regulation mechanisms of HCP5 in gliomas. HCP5 expression in glioma tumor tissues and its association with glioma patients' survival were analyzed based on RNA-sequencing data. The expression of HCP5 was also examined in glioma cells. Then, HCP5 was downregulated in U251 cells and/or primary glioblastoma cells to explore its effects on cell proliferation and migration. The influence of HCP5 downregulation on tumor growth was confirmed in xenograft mice. About the mechanism, we investigated whether HCP5 functioned via interacting with microRNA- (miR-) 205 and regulating vascular endothelial growth factor A (VEGF-A) expression in gliomas. Results showed that HCP5 upregulation was found in glioma tissues and cell lines. Patients with high HCP5 expression showed lower survival probability and shorter survival time. HCP5 downregulation inhibited cell proliferation and migration and mitigated tumor growth. miR-205 was downregulated in glioma cells. Knockdown of HCP5 led to miR-205 upregulation and VEGF-A downregulation. miR-205 overexpression exhibited the similar effects as HCP5 downregulation on cell viability and proliferation. And VEGF-A overexpression could reverse the effects of HCP5 downregulation on cell viability and proliferation, as well as tumor growth. In conclusion, HCP5 silencing suppressed glioma progression through the HCP5-miR-205-VEGF-A feedback loop.


Asunto(s)
Neoplasias Encefálicas , Glioma , MicroARNs , ARN Largo no Codificante , Factor A de Crecimiento Endotelial Vascular , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Retroalimentación , Glioma/metabolismo , Glioma/patología , Humanos , Ratones , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
14.
Gut Microbes ; 14(1): 2145843, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36398889

RESUMEN

Imbalance of gut microbiota homeostasis is related to the occurrence of ulcerative colitis (UC), and probiotics are thought to modulate immune microenvironment and repair barrier function. Here, in order to reveal the interaction between UC and gut microbiota, we screened a new probiotic strain by 16S rRNA sequencing from Dextran Sulfate Sodium (DSS)-induced colitis mice, and explored the mechanism and clinical relevance. Lactobacillus johnsonii (L. johnsonii), as a potential anti-inflammatory bacterium was decreased colonization in colitis mice. Gavage L. johnsonii could alleviate colitis by specifically increasing the proportion of intestinal macrophages and the secretion of Il-10 with macrophages depleted model and in Il10-/- mice. We identified this subset of immune cells activated by L. johnsonii as CD206+ macrophagesIL-10. Mechanistically, L. johnsonii supplementation enhanced the mobilization of CD206+ macrophagesIL-10 through the activation of STAT3 in vivo and in vitro. In addition, we revealed that TLR1/2 was essential for the activation of STAT3 and the recognition of L. johnsonii by macrophages. Clinically, there was positive correlation between the abundance of L. johnsonii and the expression level of MRC1, IL10 and TLR1/2 in UC tissues. L. johnsonii could activate native macrophages into CD206+ macrophages and release IL-10 through TLR1/2-STAT3 pathway to relieve experimental colitis. L. johnsonii may serve as an immunomodulator and anti-inflammatory therapeutic target for UC.


Asunto(s)
Colitis Ulcerosa , Colitis , Microbioma Gastrointestinal , Lactobacillus johnsonii , Receptor Toll-Like 1 , Animales , Ratones , Antiinflamatorios , Colitis/genética , Colitis/microbiología , Colitis/terapia , Colitis Ulcerosa/genética , Colitis Ulcerosa/microbiología , Colitis Ulcerosa/terapia , Sulfato de Dextran/toxicidad , Interleucina-10/genética , Macrófagos , ARN Ribosómico 16S , Receptor Toll-Like 1/genética , Receptor Toll-Like 1/metabolismo
15.
Mediators Inflamm ; 2011: 565238, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21584281

RESUMEN

The purpose of this study was to explore the effects of tumor necrosis factor-α (TNF-α) on ventricular fibrillation (VF) in rats with acute myocardial infarction (AMI). Rats were randomly classified into AMI group, sham operation group and recombinant human tumor necrosis factor receptor:Fc fusion protein (rhTNFR:Fc) group. Spontaneous and induced VFs were recorded. Monophasic action potentials (MAPs) among different zones of myocardium were recorded at eight time points before and after ligation and MAP duration dispersions (MAPDds) were calculated. Then expression of TNF-α among different myocardial zones was detected. After ligation of the left anterior descending coronary artery, total TNF-α expression in AMI group began to markedly increase at 10 min, reached a climax at 20-30 min, and then gradually decreased. The time-windows of VFs and MAPDds in the border zone performed in a similar way. At the same time-point, the expression of TNF-α in the ischemia zone was greater than that in the border zone, and little in the non-ischemia zone. Although the time windows of TNF-α expression, the MAPDds in the border zone and the occurrence of VFs in the rhTNFR:Fc group were similar to those in the AMI group, they all decreased in the rhTNFR:Fc group. Our findings demonstrate that TNF-α could enlarge the MAPDds in the border zone, and promote the onset of VFs.


Asunto(s)
Infarto del Miocardio/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Fibrilación Ventricular/metabolismo , Enfermedad Aguda , Animales , Inmunohistoquímica , Masculino , Infarto del Miocardio/genética , Miocardio/metabolismo , Reacción en Cadena de la Polimerasa , Distribución Aleatoria , Ratas , Ratas Wistar , Factor de Necrosis Tumoral alfa/genética , Fibrilación Ventricular/genética
16.
Nat Commun ; 12(1): 3654, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34135328

RESUMEN

Crystalline materials can host topological lattice defects that are robust against local deformations, and such defects can interact in interesting ways with the topological features of the underlying band structure. We design and implement a three dimensional acoustic Weyl metamaterial hosting robust modes bound to a one-dimensional topological lattice defect. The modes are related to topological features of the bulk bands, and carry nonzero orbital angular momentum locked to the direction of propagation. They span a range of axial wavenumbers defined by the projections of two bulk Weyl points to a one-dimensional subspace, in a manner analogous to the formation of Fermi arc surface states. We use acoustic experiments to probe their dispersion relation, orbital angular momentum locked waveguiding, and ability to emit acoustic vortices into free space. These results point to new possibilities for creating and exploiting topological modes in three-dimensional structures through the interplay between band topology in momentum space and topological lattice defects in real space.

17.
Nat Commun ; 12(1): 6297, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34728639

RESUMEN

The recently discovered non-Hermitian skin effect (NHSE) manifests the breakdown of current classification of topological phases in energy-nonconservative systems, and necessitates the introduction of non-Hermitian band topology. So far, all NHSE observations are based on one type of non-Hermitian band topology, in which the complex energy spectrum winds along a closed loop. As recently characterized along a synthetic dimension on a photonic platform, non-Hermitian band topology can exhibit almost arbitrary windings in momentum space, but their actual phenomena in real physical systems remain unclear. Here, we report the experimental realization of NHSE in a one-dimensional (1D) non-reciprocal acoustic crystal. With direct acoustic measurement, we demonstrate that a twisted winding, whose topology consists of two oppositely oriented loops in contact rather than a single loop, will dramatically change the NHSE, following previous predictions of unique features such as the bipolar localization and the Bloch point for a Bloch-wave-like extended state. This work reveals previously unnoticed features of NHSE, and provides the observation of physical phenomena originating from complex non-Hermitian winding topology.

18.
Sci Adv ; 7(50): eabj2062, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34878836

RESUMEN

Negative refraction is a counterintuitive wave phenomenon that has inspired the development of metamaterials and metasurfaces with negative refractive indices and surface phase discontinuities, respectively. Recent theories have proposed an alternative mechanism for negative refraction: Synthetic gauge fields, induced by either dynamical modulation or motion, can shift a material's dispersion in momentum space, forcing a positive refractive index medium to exhibit negative refraction above a certain threshold. However, this phenomenon has not previously been observed. Here, we report on the experimental demonstration of gauge field­induced negative refraction in a twisted bilayer acoustic metamaterial. The synthetic gauge fields arise in a projected two-dimensional geometry and can be continuously tuned by varying the wave number along the third dimension. Gauge field­induced waveguiding with backward-propagating modes is also demonstrated in a trilayer configuration. These results introduce a mechanism for performing wave manipulation in artificially engineered materials.

20.
Int J Med Mushrooms ; 22(10): 979-990, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33426827

RESUMEN

Some medicinal mushrooms have effects on sexual dysfunctions. Nitric oxide synthase (NOS)-cyclic gua-nosine monophosphate (cGMP)-phosphodiesterase 5 enzyme (PDE5) pathway is one of the pathophysiological basis of erectile dysfunction (ED). The normal erectile function involves the synthesis of nitric oxide (NO), and the subsequent accumulation of cGMP, whereas cGMP degradation is specifically controlled by PDE5, which promotes corporal smooth muscle cell (SMC) tone and terminates erection. The antioxidant activities of Inonotus obliquus (chaga) water extracts (IO1) and water extraction and alcohol precipitation extracts (IO2) were compared using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay and oxygen radical absorbance capacity (ORAC) method. Three subtypes of NOS (nNOS, iNOS, and eNOS) and PDE5 protein expressions were tested by Western blotting, and cGMP was determined by ELISA on a rat corporal primary SMC. The results revealed that IO2, which had a significantly higher polysaccharide content than IO1, showed a significantly higher ORAC value and a significantly lower half inhibitory concentration for DPPH scavenging activity than IO1. We observed that both IO1 and IO2 increased the expression of eNOS and iNOS significantly compared with the control. Furthermore, when compared with the control, IO1 increased PDE5 expression significantly, while IO2 showed no effect. The different impacts on PDE5 might be the reason that IO2, not IO1, showed significant inducible effect on cGMP compared with the control. This is to our knowledge, the first study exploring the effect of I. obliquus on NOS-cGMP-PDE5 pathway on SMC. The results provide a possible selection of I. obliquus for the treatment of ED.


Asunto(s)
Agaricales/química , GMP Cíclico/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , Disfunción Eréctil/metabolismo , Inonotus/química , Miocitos del Músculo Liso/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Extractos Vegetales/farmacología , Animales , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/genética , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/genética , Disfunción Eréctil/fisiopatología , Humanos , Masculino , Miocitos del Músculo Liso/metabolismo , Óxido Nítrico Sintasa/genética , Pene/metabolismo , Pene/fisiopatología , Ratas
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