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1.
J Colloid Interface Sci ; 663: 825-833, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447397

RESUMEN

Graphitic carbon nitride (g-C3N4, CN) has garnered considerable attention in the field of photocatalysis due to its favorable band gap and high specific surface area. However, its primary practical limitation lies in the strong radiative recombination of lone pair (LP) electronic states, leading to limited efficiency in separating photogenerated carriers and subsequently diminishing photocatalytic performance. In this study, we devised and synthesized a heterojunction photocatalytic system comprising TiO2 nanosheets supported on modified g-C3N4 (MCN), designated as MCN/TiO2. The presence of CN functional groups on the tri-s-triazine nitrogen captures photogenerated electrons by modifying LP electronic states, resulting in a reduction in the fluorescence emission intensity of g-C3N4. Simultaneously, it forms chemical bonds with the supported TiO2 nanosheets, creating an efficient electron transfer pathway for the accumulation of photogenerated electrons at the active Ti sites. Experimentally, the MCN/TiO2 photocatalytic system exhibited optimal performance in CO2 reduction. The CH4 production rate reached 26.59 µmol g-1 h-1, surpassing that of TiO2 and CN/TiO2 by approximately 8 and 3 times, respectively. Furthermore, this photocatalytic system demonstrated exceptional photostability over five cycles, each lasting 4 h. This research offers a valuable approach for the efficient separation and transfer of photogenerated carriers in composite materials based on g-C3N4.

2.
Nano Lett ; 24(11): 3525-3531, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38466128

RESUMEN

Variegation and complexity of polarization relaxation loss in many heterostructured materials provide available mechanisms to seek a strong electromagnetic wave (EMW) absorption performance. Here we construct a unique heterostructured compound that bonds α-Fe2O3 nanosheets of the (110) plane on carbon microtubes (CMTs). Through effective alignment between the Fermi energy level of CMTs and the conduction band position of α-Fe2O3 nanosheets at the interface, we attain substantial polarization relaxation loss via novel atomic valence reversal between Fe(III) ↔ Fe(III-) induced with periodic electron injection from conductive CMTs under EMW irradiation to give α-Fe2O3 nanosheets. Such heterostructured materials possess currently reported minimum reflection loss of -84.01 dB centered at 10.99 GHz at a thickness of 3.19 mm and an effective absorption bandwidth (reflection loss ≤ -10 dB) of 7.17 GHz (10.83-18 GHz) at 2.65 mm. This work provides an effective strategy for designing strong EMW absorbers by combining highly efficient electron injection and atomic valence reversal.

3.
PLoS One ; 19(2): e0296997, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38330030

RESUMEN

A dynamic STIRPAT model used in the current study is based on panel data from the eight most populous countries from 1975 to 2020, revealing the nonlinear effects of urbanization routes (percentage of total urbanization, percentage of small cities and percentage of large cities) on carbon dioxide (CO2) emissions. Using "Dynamic Display Unrelated Regression (DSUR)" and "Fully Modified Ordinary Least Squares (FMOLS)" regressions, the outcomes reflect that percentage of total urbanization and percentage of small cities have an incremental influence on carbon dioxide emissions. However, square percentage of small cities and square percentage of total urbanization have significant adverse effects on carbon dioxide (CO2) emissions. The positive relationship between the percentage of small cities, percentage of total urbanization and CO2 emissions and the negative relationship between the square percentage of small cities, square percentage of total urbanization and CO2 emissions legitimize the inverted U-shaped EKC hypothesis. The impact of the percentage of large cities on carbon dioxide emissions is significantly negative, while the impact of the square percentage of large cities on carbon dioxide emissions is significantly positive, validating a U-shaped EKC hypothesis. The incremental effect of percentage of small cities and percentage of total urbanization on long-term environmental degradation can provide support for ecological modernization theory. Energy intensity, Gross Domestic Product (GDP), industrial growth and transport infrastructure stimulate long-term CO2 emissions. Country-level findings from the AMG estimator support a U-shaped link between the percentage of small cities and CO2 emissions for each country in the entire panel except the United States. In addition, the Dumitrescu and Hulin causality tests yield a two-way causality between emission of carbon dioxide and squared percentage of total urbanization, between the percentage of the large cities and emission of carbon dioxide, and between energy intensity and emission of carbon dioxide. This study proposes renewable energy options and green city-friendly technologies to improve the environmental quality of urban areas.


Asunto(s)
Dióxido de Carbono , Urbanización , Dióxido de Carbono/análisis , Ciudades , Producto Interno Bruto , Análisis de los Mínimos Cuadrados , Desarrollo Económico
4.
Int J Biol Macromol ; 251: 126394, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37595700

RESUMEN

The semi-rigidity of the polylactic acid (PLA) molecular chain makes it brittle, poor impact resistance and barrier properties, which severely limits its practical applications. In this paper, a bio-based reactive plasticizer epoxy soybean oil (ESO) was used to improve the mechanical and barrier properties of maleic anhydride grafted polylactic acid (MAPLA) by the chemical reaction between the epoxy and anhydride group. Firstly, the optimum curing conditions were 93.5 °C, 100 °C, and 110.8 °C for 2 h. The effects of different mass fractions of ESO on the properties of MAPLA-ESO (ME) films were systematically investigated. It was found that when the content of ESO was 10 wt%, the tensile properties of the resulting ME films were the best, with a tensile strength of 35.2 MPa. And it had an elongation at break of 20.0 % and toughness of 5.4 MJ/m3, which increased to 690 % and 675 %, respectively, compared with pure MAPLA films. The chemically crosslinked ME films also displayed excellent water resistance, well degradation, low migration properties, and better performance than that of commercial paper straws and PLA straws, exhibiting great application potential as degradable disposable straws. Therefore, this work provides an effective way to develop high-performance, green, and degradable PLA films and products.

5.
Gut Pathog ; 15(1): 38, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37518066

RESUMEN

BACKGROUND: The day-to-day (DTD) management model encourages patients to actively participate in their healthcare by setting goals. We determined the effectiveness of the DTD model in the treatment of Helicobacter pylori (H. pylori) infection, as compared with conventional outpatient education (OE). METHODS: We randomized 254 H. pylori-positive patients into a DTD group (127 patients) and an OE group (127 patients) prior to primary treatment with 14-day bismuth-containing quadruple therapy, including esomeprazole, amoxicillin, and clarithromycin. Both groups received consistent medication instructions. Patients in the DTD group recorded daily attendance after completing their daily medication plan from day 1 to day 14. The medication compliance, follow-up compliance, H. pylori eradication rates, and adverse events (AEs) were evaluated. RESULTS: In the modified intention-to-treat (MITT) and per-protocol (PP) analyses, the DTD group showed significantly higher medication compliance than the OE group (P = 0.001 and P = 0.031, respectively). Both the MITT and PP analyses showed significant differences in follow-up compliance (P < 0.001 and P = 0.003, respectively) and timing of the review urea breath test (P < 0.001 and P = 0.001, respectively) between the two groups. However, no significant differences were observed in the H. pylori eradication rates (95.8% vs. 93.8%, P = 0.529) in the PP analysis, or AEs incidence (25.4% vs. 28.3%, P = 0.603) between the two groups. CONCLUSION: This study demonstrated the novel application of the DTD model in the treatment of H. pylori infection, which enabled patients to develop habitual medication-taking behaviors without physician intervention.

6.
Biol Res ; 56(1): 16, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005678

RESUMEN

BACKGROUND/AIMS: Diabetes mellitus (DM) is highly susceptible to diabetic hind limb ischemia (DHI). MicroRNA (MiR)-17-5p is downregulated in DM and plays a key role in vascular protection. Endothelial progenitor cell (EPC)-released exosomes (EPC-EXs) contribute to vascular protection and ischemic tissue repair by transferring their contained miRs to target cells. Here, we investigated whether miR-17-5p-enriched EPC-EXs (EPC-EXsmiR-17-5p) had conspicuous effects on protecting vascular and skeletal muscle in DHI in vitro and in vivo. METHODS: EPCs transfected with scrambled control or miR-17-5p mimics were used to generate EPC-EXs and EPC-EXsmiR-17-5p. Db/db mice were subjected to hind limb ischemia. After the surgery, EPC-EXs and EPC-EXsmiR-17-5p were injected into the gastrocnemius muscle of the hind limb once every 7 days for 3 weeks. Blood flow, microvessel density, capillary angiogenesis, gastrocnemius muscle weight, structure integrity, and apoptosis in the hind limb were assessed. Vascular endothelial cells (ECs) and myoblast cells (C2C12 cells) were subjected to hypoxia plus high glucose (HG) and cocultured with EPC-EXs and EPC-EXsmiR-17-5p. A bioinformatics assay was used to analyze the potential target gene of miR-17-5p, the levels of SPRED1, PI3K, phosphorylated Akt, cleaved caspase-9 and cleaved caspase-3 were measured, and a PI3K inhibitor (LY294002) was used for pathway analysis. RESULTS: In the DHI mouse model, miR-17-5p was markedly decreased in hind limb vessels and muscle tissues, and infusion of EPC-EXsmiR-17-5p was more effective than EPC-EXs in increasing miR-17-5p levels, blood flow, microvessel density, and capillary angiogenesis, as well as in promoting muscle weight, force production and structural integrity while reducing apoptosis in gastrocnemius muscle. In Hypoxia plus HG-injured ECs and C2C12 cells, we found that EPC-EXsmiR-17-5p could deliver their carried miR-17-5p into target ECs and C2C12 cells and subsequently downregulate the target protein SPRED1 while increasing the levels of PI3K and phosphorylated Akt. EPC-EXsmiR-17-5p were more effective than EPC-EXs in decreasing apoptosis and necrosis while increasing viability, migration, and tube formation in Hypoxia plus HG-injured ECs and in decreasing apoptosis while increasing viability and myotube formation in C2C12 cells. These effects of EPC-EXsmiR-17-5p could be abolished by a PI3K inhibitor (LY294002). CONCLUSION: Our results suggest that miR-17-5p promotes the beneficial effects of EPC-EXs on DHI by protecting vascular ECs and muscle cell functions.


Asunto(s)
Diabetes Mellitus , MicroARNs , Ratones , Animales , Células Endoteliales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas , Movimiento Celular , Músculo Esquelético/metabolismo , Isquemia , MicroARNs/genética , MicroARNs/metabolismo , Hipoxia
7.
Nano Lett ; 23(9): 3694-3700, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37074399

RESUMEN

Peroxide dianion (O22-) has strong oxidizing activity and ease of proton abstraction and is extremely unstable. Direct and controllable adsorption and release of O22- has large application implication and is a large challenge so far. Here, we use a unique metal (Ni)-organic (diphenylalanine, DPA) framework (MOF), Ni(DPA)2, as adsorbents for absorption and release of O22-. This MOF structure has room-temperature magnetoelectricity via distortion of the Ni-centered octahedron {NiN2O4} and thus possesses a tunable ferroelectric polarization under applied electric/magnetic fields. Controllable adsorption and release of O22- are realized in such a MOF system via electrochemical redox measurements. Structural/spectroscopic characterization and calculations reveal that a number of NH active sites in the nanopores of MOF can effectively adsorb O22- by hydrogen bonds and then tunable ferroelectric polarization induces controllable release of O22- under applied magnetic fields. This work presents a constructive way for controllable adsorption and release of reactive oxygen species.

8.
J Colloid Interface Sci ; 642: 505-512, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37028157

RESUMEN

The electrochemical oxygen evolution reaction is a bottleneck reaction in hydrolysis and electrolysis because the four-step electron transfer leads to slow reaction kinetics and large overpotentials. This situation can be improved by fast charge transfer by optimizing the interfacial electronic structure and enhancing polarization. Herein, a unique metal (Ni) organic (diphenylalanine, DPA) framework Ni(DPA)2 (Ni-MOF) with tunable polarization is designed to bond with FeNi-LDH (layered double hydroxides) nanoflakes. The Ni-MOF@FeNi-LDH heterostructure delivers excellent oxygen evolution performance exemplified by an ultralow overpotential of 198 mV at 100 mA cm-2 compared to other (FeNi-LDH)-based catalysts. Experiments and theoretical calculations show that FeNi-LDH exists in an electron-rich state in Ni-MOF@FeNi-LDH due to polarization enhancement caused by interfacial bonding with Ni-MOF. This effectively changes the local electronic structure of the metal Fe/Ni active sites and optimizes adsorption of the oxygen-containing intermediates. Polarization and electron transfer of Ni-MOF are further enhanced by magnetoelectric coupling consequently giving rise to better electrocatalytic properties as a result of high-density electron transfer to active sites. These findings reveal a promising interface and polarization modulation strategy to improve electrocatalysis.

9.
Am J Gastroenterol ; 118(4): 627-634, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36729890

RESUMEN

INTRODUCTION: No study has investigated the efficacy and safety of vonoprazan-amoxicillin dual therapy compared with bismuth quadruple therapy (B-quadruple). This study aimed to evaluate the efficacy and safety of 10-day vonoprazan-amoxicillin dual therapy as a first-line treatment of Helicobacter pylori infection compared with B-quadruple and to explore the optimal dosage of amoxicillin in the dual therapy. METHODS: A total of 375 treatment-naive, H. pylori -infected subjects were randomly assigned in a 1:1:1 ratio into 3 regimen groups including VHA-dual (vonoprazan 20 mg twice/day + amoxicillin 750 mg 4 times/day), VA-dual (vonoprazan 20 mg + amoxicillin 1,000 mg twice/day), and B-quadruple (esomeprazole 20 mg + bismuth 200 mg + amoxicillin 1,000 mg + clarithromycin 500 mg twice/day). Eradication rates, adverse events (AEs), and compliance were compared between 3 groups. RESULTS: The eradication rates of B-quadruple, VHA-dual, and VA-dual were 90.9%, 93.4%, and 85.1%, respectively, by per-protocol analysis; 89.4%, 92.7%, and 84.4%, respectively, by modified intention-to-treat analysis; 88.0%, 91.2%, and 82.4%, respectively, by intention-to-treat analysis. The efficacy of the VHA-dual group was not inferior to the B-quadruple group ( P < 0.001), but VA-dual did not reach a noninferiority margin of -10%. The AEs rates of the B-quadruple group were significantly higher than those of the VHA-dual ( P = 0.012) and VA-dual ( P = 0.001) groups. There was no significant difference in medication compliance among 3 treatment groups ( P = 0.995). CONCLUSIONS: The 10-day VHA-dual therapy provided satisfactory eradication rates of >90%, lower AEs rates, and similar adherence compared with B-quadruple therapy as a first-line therapy for H. pylori infection. However, the efficacy of VA-dual therapy was not acceptable.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Infecciones por Helicobacter/tratamiento farmacológico , Amoxicilina/uso terapéutico , Bismuto/uso terapéutico , Antibacterianos , Quimioterapia Combinada , Claritromicina/uso terapéutico , Resultado del Tratamiento , Inhibidores de la Bomba de Protones/efectos adversos
10.
Exp Neurol ; 359: 114235, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36174747

RESUMEN

BACKGROUNDS/AIMS: Neural progenitor cells (NPCs) and endothelial progenitor cell (EPCs) exhibit synergistical effects on protecting endothelial cell functions. MiR-126 and miR-210 can protect cell activities by regulating brain-derived neurotrophic factor (BDNF) and reactive oxygen species (ROS) production. Exosomes (EXs) mediate the beneficial effects of stem cells via delivering microRNAs (miRs). Here, we investigated the combination effects of EXs from EPCs (EPC-EXs) and NPCs (NPC-EXs), and determined whether these EXs with miR-126 (EPC-EXsmiR-126) and miR-210 overexpression (NPC-EXsmiR-210) had better effects on hypoxia/reoxygenation (H/R)-injured neurons and ischemic stroke (IS). METHODS: Cultured neurons were subjected to hypoxia for 6 h and then co-cultured with culture medium, NPC-EXs, EPC-EXs, NPC-EXs + EPC-EXs or NPC-EXsmiR-210 + EPC-EXsmiR-126 under normoxia for 24 h. Cell apoptosis, ROS production, neurite outgrowth and BDNF level were analyzed. Permanent middle cerebral artery occlusion (MCAO) was performed on C57BL/6 mice to build IS model. The mice were injected with PBS or various EXs via tail vein 2 h after MCAO operation. After 24 h, infarct volume and neurological deficits score (NDS), neuronal apoptosis, ROS production and spine density of dendrites, and brain BDNF level were analyzed. For mechanism study, NADPH oxidase 2(Nox2) and BDNF receptor tyrosine kinase receptor B (TrkB) were determined, and TrkB inhibitor k-252a was used in in vitro and in vivo study. RESULTS: 1) The level of miR-210 or miR-126 was increased after NPC-EXs or EPC-EXs treatment respectively. 2) In H/R-injured neurons, NPC-EXs or EPC-EXs decreased cell apoptosis and ROS production and promoted neurite outgrowth, which were associated with the downregulation of Nox2 and the increase of BDNF and p-TrkB/TrkB level. 3) In MCAO mice, NPC-EXs or EPC-EXs decreased infarct volume and NDS, reduced neural apoptosis and ROS production, and promoted the spine density of dendrites. The levels of Nox2, BDNF and p-TrkB/TrkB in mouse brain tissues changed in similar patterns as seen in the in vitro study. 4) In both cell and mouse models, combination of NPC-EXs and EPC-EXs was more effective than NPC-EXs or EPC-EXs alone on all of these effects. 5) EPC-EXsmiR-126 + NPC-EXsmiR-210 had better effects compared to NPC-EXs + EPC-EXs, which were inhibited by k-252a. CONCLUSION: EPC-EXsmiR-126 combined NPC-EXsmiR-210 further orchestrate the combinative protective effects of EPC-EXs and NPC-EXs on IS, possibly by protecting H/R-injured neurons through the Nox2/ ROS and BDNF/TrkB pathways.


Asunto(s)
Células Progenitoras Endoteliales , Exosomas , Accidente Cerebrovascular Isquémico , MicroARNs , Animales , Ratones , Apoptosis , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Células Progenitoras Endoteliales/metabolismo , Exosomas/metabolismo , Hipoxia/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Neuronas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
11.
Biol. Res ; 56: 16-16, 2023. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-1439483

RESUMEN

BACKGROUND/AIMS: Diabetes mellitus (DM) is highly susceptible to diabetic hind limb ischemia (DHI). MicroRNA (MiR)-17-5p is downregulated in DM and plays a key role in vascular protection. Endothelial progenitor cell (EPC)-released exosomes (EPC-EXs) contribute to vascular protection and ischemic tissue repair by transferring their contained miRs to target cells. Here, we investigated whether miR-17-5p-enriched EPC-EXs (EPC-EXsmiR-17-5p) had conspicuous effects on protecting vascular and skeletal muscle in DHI in vitro and in vivo. METHODS: EPCs transfected with scrambled control or miR-17-5p mimics were used to generate EPC-EXs and EPC-EXsmiR-17-5p. Db/db mice were subjected to hind limb ischemia. After the surgery, EPC-EXs and EPC-EXsmiR-17-5p were injected into the gastrocnemius muscle of the hind limb once every 7 days for 3 weeks. Blood flow, microvessel density, capillary angiogenesis, gastrocnemius muscle weight, structure integrity, and apoptosis in the hind limb were assessed. Vascular endothelial cells (ECs) and myoblast cells (C2C12 cells) were subjected to hypoxia plus high glucose (HG) and cocultured with EPC-EXs and EPC-EXsmiR-17-5p. A bioinformatics assay was used to analyze the potential target gene of miR-17-5p, the levels of SPRED1, PI3K, phosphorylated Akt, cleaved caspase-9 and cleaved caspase-3 were measured, and a PI3K inhibitor (LY294002) was used for pathway analysis. RESULTS: In the DHI mouse model, miR-17-5p was markedly decreased in hind limb vessels and muscle tissues, and infusion of EPC-EXsmiR-17-5p was more effective than EPC-EXs in increasing miR-17-5p levels, blood flow, microvessel density, and capillary angiogenesis, as well as in promoting muscle weight, force production and structural integrity while reducing apoptosis in gastrocnemius muscle. In Hypoxia plus HG-injured ECs and C2C12 cells, we found that EPC-EXsmiR-17-5p could deliver their carried miR-17-5p into target ECs and C2C12 cells and subsequently downregulate the target protein SPRED1 while increasing the levels of PI3K and phosphorylated Akt. EPC-EXsmiR-17-5p were more effective than EPC-EXs in decreasing apoptosis and necrosis while increasing viability, migration, and tube formation in Hypoxia plus HG-injured ECs and in decreasing apoptosis while increasing viability and myotube formation in C2C12 cells. These effects of EPC-EXsmiR-17-5p could be abolished by a PI3K inhibitor (LY294002). CONCLUSION: Our results suggest that miR-17-5p promotes the beneficial effects of EPC-EXs on DHI by protecting vascular ECs and muscle cell functions.


Asunto(s)
Animales , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Diabetes Mellitus , Movimiento Celular , Músculo Esquelético/metabolismo , Fosfatidilinositol 3-Quinasas , Células Endoteliales , Isquemia , Hipoxia
12.
ACS Appl Mater Interfaces ; 14(48): 54328-54337, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36399665

RESUMEN

Truncated octahedron Cu2O (TOC) has attracted more attention for its suitable band gap and high carrier separation efficiency due to introduction of the facet heterojunction, but its practical drawback is still the instability caused by the irreversible disproportionation reaction (Cu2O → Cu + CuO). Here, we design and fabricate the TOC/Cu-MOF (MOF: metal-organic framework) double-heterojunction structures with different Cu-MOF loadings. The introduced heterojunction between TOC and Cu-MOF not only produces a stable interface Cux+ bonding structure with the electronic states localized within the average collisional diameter of electrons 1.72 nm for TOC/2.1 wt %Cu-MOF as the active sites, but also promotes the surface energy level difference between the (100) and (111) facet heterojunctions. Meanwhile, the bonded Cu-MOF with a narrow bandgap effectively consumes holes by recombination with the photoexcited electrons from Cu-MOF itself. In our experiments, the TOC/Cu-MOF double heterostructure with a loading amount of 2.1 wt % Cu-MOF shows an optimal photocatalytic CO2 reduction performance. The CO evolution rate reaches 23.01 µmol g-1 h-1, which is about 2.01 and 4.47 times larger than those of octahedral and hexahedral Cu2O/Cu-MOF, respectively, and an excellent photostability is shown for four cycles with each cycle lasting for 4 h. Such a double heterostructure provides insight into highly efficient electron transfer and photostability in Cu2O-related composite materials.

13.
Front Bioeng Biotechnol ; 10: 948230, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36420442

RESUMEN

Investigations of pulsatile tinnitus (PT) caused by sigmoid sinus wall anomalies (SSWAs) using computational fluid dynamics (CFD) have recently increased in prevalence. However, accurate modeling of anatomical structures regarding sigmoid plate dehiscence and acoustic sources of PT remains lacking. This study incorporates coupled CFD techniques, micro-computed tomography, and scanning electron microscope to reveal the vibroacoustic and hydroacoustic sources and displacement characteristics of the transverse-sigmoid sinus system. Furthermore, the in vivo transcanal-recording technique combined with ipsilateral internal jugular vein compression was implemented to cross-reference the captured acoustic profile of PT with the calculated results. In this study, the transient state coupled CFD technique was used to calculate the vibroacoustic and hydroacoustic sources. The dehiscent sigmoid plate and periosteal dura mater were then reconstructed. The displacement characteristics and acoustic results were analyzed. The displacement of the vascular wall underneath the dehiscent area was 9.6 times larger than that of the sigmoid plate and 3,617 times smaller than that of the vascular wall without the overlying osseous structures. The peak amplitude of flow-induced vibroacoustic noise was 119.3 dB at 20.2 Hz measured at the transverse sinus. Within the observed 20-1,000 Hz frequency range, the largest peak amplitude of hydroacoustic noise was 80.0 dB at 20.2 Hz located at the jugular bulb region. The simulated results conformed with the in vivo acoustic profile which the major frequency of PT falls within 1,000 Hz. In conclusion, 1) the sigmoid plate and dura mater greatly impact vascular wall displacement, which should not be overlooked in CFD simulations. 2) By incorporating the transcanal recording technique with IJV compression test, the primary frequency of PT was found fluctuating below 1,000 Hz, which matches the frequency component simulated by the current CFD technique; amplitude-wise, however, the peak amplitude of in vivo pulse-synchronous somatosound measures approximately 10 dB, which is comparatively lesser than the CFD results and the subjectively perceived loudness of PT. Thus, the transmission pathway, intramastoid acoustic impedance/amplification effect, and the perceptive threshold of PT require further investigations to minimize the incidence of surgical failure.

14.
Small ; 18(42): e2204456, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36116118

RESUMEN

An RhFe bimetallene with Fe atoms doped into Rh host for efficient hydrogen evolution reaction (HER), is constructed. When two doped Fe atoms occupy neighboring asymmetric spatial positions, their asymmetric exchange interaction drives electron hopping between the dxy orbital of a Fe atom and the dz 2 orbital of its neighboring Fe atom to push the d band center closer to the Fermi level as a result of electronic state reconstruction. The designed bimetallene with thickness of 0.77 nm (5 atomic layers), possesses excellent HER performance. The low overpotentials of 24.4 and 34.6 mV are achieved at the 10 and 100 mA cm-2 current densities in 1 m KOH solution, respectively. An ultra-low Tafel slope of 8.9 mV dec-1 shows that this kind of RhFe bimetallene is of an ultrafast kinetic process. This work provides a strategy for designing HER catalysts with double metal composites.

15.
Front Psychol ; 13: 908736, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783792

RESUMEN

Counterfactual thinking is presumed to play a preparatory function in promoting people's behavioural intentions. This study specifically addresses the impacts of COVID-19 severity, tourists' counterfactual thinking about the pandemic, and tourists' perceived duty-free consumption value on the effect of a duty-free policy on travel intentions. Four hundred and ten participants took part in this study, which involved a 2 (duty-free policy: absent vs. present) × 2 (COVID-19 severity: high vs. low) design. Results reveal the following patterns: (a) compared to the absence of a duty-free policy in tourist destinations, enactment of a duty-free policy leads to stronger visit intentions through greater perceived value and (b) the effect of a duty-free policy on travel intention is moderated by tourists' counterfactual thinking and COVID-19 severity.

16.
Minerva Pediatr (Torino) ; 74(5): 530-536, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-32686922

RESUMEN

BACKGROUND: The purpose of this study was to investigate and analyze the difficulties and the influencing factors in the laparoscopic surgery for appendiceal abscess in children. METHODS: Forty-six patients with appendiceal abscess receiving laparoscopic surgery (laparoscopic surgery group) in Xuzhou Children's Hospital from January 2012 to March 2017 were retrospectively analyzed. The surgery was performed using the 3-hole method, the 30° lens was placed in umbilical region, and the left lower abdomen and superior pubis were the operating holes. If the appendix was thick and big, 10 mm trocar was replaced on the superior pubis and the appendix was removed, followed by pelvic or lower abdominal drainage via the superior pubis incision. RESULTS: The laparoscopic surgery group was compared with 45 cases of laparotomy (traditional surgery group) for appendiceal abscess performed by the same group of operators in the past, and the perioperative period and postoperative complications between the two groups were compared. The child patients' age, history of abdominal pain and prediagnosis treatment were compared within the laparoscopic surgery group. Compared with those in traditional surgery group, the surgery time in laparoscopic surgery group had no statistically significant difference (P>0.05), the incidence rate of complications was lower, and the difference was statistically significant (P<0.05). In laparoscopic surgery group, the surgery time of child patients aged ≥6 years old with the medical history for more than 5 days and unreasonable preoperative treatment was longer than that of child patients aged <6 years old with the medical history for less than or equal to 5 days and reasonable preoperative treatment, and the difference was statistically significant (P<0.05). CONCLUSIONS: Compared with the traditional surgery, laparoscopic surgery for appendiceal abscess in children can significantly reduce the postoperative complications; at the same time, the history of abdominal pain and preoperative treatment are the influencing factors of surgery.


Asunto(s)
Enfermedades Intestinales , Laparoscopía , Niño , Humanos , Apendicectomía/efectos adversos , Apendicectomía/métodos , Absceso/cirugía , Absceso/complicaciones , Estudios Retrospectivos , Tiempo de Internación , Resultado del Tratamiento , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Enfermedades Intestinales/complicaciones , Enfermedades Intestinales/cirugía , Dolor Abdominal/complicaciones , Dolor Abdominal/cirugía
17.
ORL J Otorhinolaryngol Relat Spec ; 84(3): 219-228, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34311465

RESUMEN

OBJECTIVE: Venous pulsatile tinnitus (PT) has received increasing attention recently. As analyses of psychophysical and neuropsychological dimensions of venous PT are lacking, this study aimed to quantitatively and qualitatively investigate the correlation among audiometric, hydroacoustic, and subjective outcomes in patients with PT. METHODS: Fifty-five venous PT patients, with or without sigmoid sinus wall anomalies (SSWAs), were subdivided into SSWAs (n = 30) and non-SSWAs (n = 25) groups. Audiometric and hemodynamic evaluations were assessed. Questionnaires including the Tinnitus Handicap Inventory, Hospital Anxiety and Depression Scale (HADS), and Athens Insomnia Scale (AIS) were deployed to evaluate the psychological impacts of PT. RESULTS: Among 55 subjects, PT frequency-related pure-tone audiometry (PTA) was significantly different between ipsilesional non-PT frequency-related PTA (p < 0.01), ipsilateral jugular vein compression PTA (p < 0.01), and contralesional ear PTA (p < 0.01). In contrast with the pulsatility index and flow velocity, bilateral EOET and flow volume were significantly different (p < 0.01). Of the 3 questionnaire types, there was a strong correlation between HADS anxiety and AIS scores (r = 0.658, p < 0.01). The duration of PT was not correlated with subjective outcomes, and there was no statistical significance found among audiometric, hemodynamic, and subjective outcomes between SSWAs and non-SSWAs groups. CONCLUSIONS: (1) The duration of PT was irrelevant to the increase of PTA. (2) Venous PT is the perception of vascular flow sound, in which hydroacoustic characteristics can be highly independent. (3) Anxiety, depression, and sleep disorders commonly prevail among PT patients.


Asunto(s)
Senos Paranasales , Acúfeno , Audiometría de Tonos Puros , Senos Craneales/anomalías , Senos Craneales/diagnóstico por imagen , Humanos , Acúfeno/diagnóstico por imagen , Ultrasonografía Doppler
18.
Laryngoscope Investig Otolaryngol ; 6(6): 1436-1448, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34938885

RESUMEN

OBJECTIVES: (1) To establish evidence of the transmission pathway of venous pulsatile tinnitus (PT) associated with sigmoid sinus wall anomalies (SSWAs) and (2) quantify the efficacy of transtemporal surgery. METHODS: This retrospective study included 33 surgical cases of PT associated with SSWAs and 15 controls with venous PT without SSWAs. Quantitative water occlusion test (q-WOT) and imaging data were acquired for preoperative evaluation prior to strategized transtemporal osteovascular reconstruction surgery. A condenser microphone and hydrophone were intraoperatively deployed to assess and monitor in vivo amplitude variations of the PT in eight participants. RESULTS: A total of 23 (69.6%) participants with SSWA responded to the q-WOT with a median solution volume of 1.3 (1.1/1.6), which significantly differed from that observed in controls (p < 0.01). The change in the operative peak amplitude of the acoustic data was statistically significant (p < 0.01), from a median of 57.6 (55.5/57.9) dB SPL to 34.3 (33.4/38.8) dB SPL. CONCLUSION: Intraoperative application of acoustic sensors revealed that PT associated with SSWAs is predominantly transmitted via the air-conduction pathway. If objective findings such as q-WOT and sensing applications suggest that the transmission of venous PT is involved in middle ear air conduction, the reconstruction technique should be prioritized; if less involvement of middle ear air-conduction is indicated, addressing flow pathologies may be imperative for resolving venous PT. LEVEL OF EVIDENCE: 4.

19.
Exp Cell Res ; 407(2): 112808, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34508744

RESUMEN

Regulatory T (Treg) cells are thought to contribute to tumor pathogenesis by suppressing tumor immunosurveillance and antitumor immunity. T follicular regulatory (Tfr) cells are a recently characterized Treg subset that expresses both the Treg transcription factor (TF) Foxp3 and the T follicular helper (Tfh) TF Bcl-6. The role of Tfr cells in glioma patients remains unclear. In this study, we found that the level of Tfr cells, identified as Foxp3+Bcl-6+ CD4 T cells, was significantly elevated in tumor-infiltrating CD4 T cells from resected glioma tumors. Both Tfr cells and Treg cells significantly suppressed the proliferation and the cytotoxic capacity of CD8 T cells toward glioma tumor cells, and the suppression was positively associated with the proportion of Tfr cells and Treg cells, respectively. Tfr and Treg cells from glioma tumor samples demonstrated higher suppression potency than those from healthy blood samples and glioma blood samples. Interestingly, canonical CXCR5- Treg cells could suppress both CXCR5+ and CXCR5- CD8 T cells, albeit with stronger potency toward CXCR5- CD8 T cells. However, Tfr cells presented much higher suppression potency toward CXCR5+ CD8 T cells, whereas CXCR5+ CD8 T cells are a potent CD8 T cell subset previously described to have antiviral and antitumor roles. Overall, these data indicate that Tfr cells are enriched in glioma tumors and have suppressive capacity toward CD8 T cell-mediated effector functions.


Asunto(s)
Neoplasias Encefálicas/inmunología , Linfocitos T CD8-positivos/inmunología , Glioma/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Reguladores/inmunología , Adolescente , Adulto , Anciano , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Femenino , Glioma/metabolismo , Glioma/patología , Humanos , Masculino , Persona de Mediana Edad , Células Tumorales Cultivadas , Adulto Joven
20.
J Gene Med ; 23(10): e3371, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34105224

RESUMEN

BACKGROUND: As the most common and detrimental brain tumor with high invasiveness and poor prognosis, glioblastoma (GBM) has severely threatened people's health globally. Therefore, it is of great importance and necessary to identify the molecular mechanisms involved in tumorigenesis and development, thus contributing to potential therapeutic targets and strategies. METHODS: The level of circ_0001588 was detected in 68 pairs of GBM tissues and adjacent normal tissues and human glioma cell lines via a real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Then, the effect of circ_0001588 on the proliferation, migration and invasion of glioma cells was evaluated. In addition, potential downstream targets of circ_0001588 were forecasted by circBANK and Starbase. Their interaction was confirmed by introducing luciferase reporter assays. Moreover, sh-circ_0001588 transfected U251 cells were used to form tumors in vivo. Finally, the functional mechanism of circ_0001588 was identified by qRT-PCR, western blotting, xenograft and immunohistochemistry (IHC) assays. RESULTS: The expression of circ_0001588 is markedly up-regulated in GBM tissues and human gliomas cells. Additionally, increased expression of circ_0001588 is positively relevant with poor survival in GBM patients. The down-regulation of circ_0001588 distinctly inhibits the proliferation, migration and invasion of GBM in vitro, as well as tumor growth in vivo. Moreover, knockdown of circ_0001588 reduces the tumor volume and weight, enhances the relative IHC staining index of E-cadherin and decreases the relative IHC staining index of Ki-67, Yin Yang 1 (YY1) and vinmentin in vivo. Mechanistically, circ_0001588 locates in the cytoplasm, which is directly bound with miR-211-5p. Furthermore, circ_0001588 can positively regulate YY1 via sponging miR-211-5p. Moreover, circ_0001588 accelerates the proliferation, migration and invasion of GBM by modulating miR-211-5p/YY1 signaling. CONCLUSIONS: These results illustrate a new circ_0001588/miR-211-5p/YY1 regulatory signaling axis in GBM.


Asunto(s)
Neoplasias Encefálicas/genética , Regulación Neoplásica de la Expresión Génica/genética , Glioblastoma/genética , MicroARNs/genética , ARN Circular/genética , Regulación hacia Arriba/genética , Factor de Transcripción YY1/genética , Apoptosis/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Progresión de la Enfermedad , Regulación hacia Abajo/genética , Glioblastoma/patología , Glioma/genética , Glioma/patología , Humanos
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