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1.
Small ; 19(25): e2208045, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929607

RESUMO

Alkaline membrane water electrolysis is a promising production technology, and advanced electrocatalyst and membrane electrode design have always been the core technology. Herein, an ion-exchange method and an environmentally friendly in situ green phosphating strategy are successively employed to fabricate Ru-Ru2 P heterogeneous nanoparticles by using hydroxyapatite (HAP) as a phosphorus source, which is an exceptionally active electrocatalyst for hydrogen evolution reaction (HER). Density functional theory calculation results reveal that strong electronic redistribution occurs at the heterointerface of Ru-Ru2 P, which modulates the electronic structure to achieve an optimized hydrogen adsorption strength. The obtained Ru-Ru2 P possesses excellent HER performance (24 mV at 10 mA cm-2 ) and robust stability (1000 mA cm-2 for 120 h) in alkaline media. Furthermore, an environmentally friendly membrane electrode with a sandwich structure is assembled by HAP nanowires as an alkaline membrane, Ru-Ru2 P as a cathodic catalyst, and NiFe-LDH as an anodic catalyst, respectively. The voltage of (-) Ru-Ru2 P || NiFe-LDH/CNTs (+) (1.53 V at 10 mA cm-2 ) is lower than that of (-) 20 wt% Pt/C || RuO2 (+) (1.60 V at 10 mA cm-2 ) for overall water splitting. Overall, the studies not only design an efficient catalyst but also provide a new route to achieve a high-stability electrolyzer for industrial H2 production.

2.
Opt Express ; 31(18): 28963-28978, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710705

RESUMO

Achieving single-band upconversion (UC) is a challenging but rewarding approach to attain optimal performance in diverse applications. In this paper, we successfully achieved single-band red UC luminescence in Yb2O3: Er transparent ceramics (TCs) through the utilization of a sensitizer-rich design. The Yb2O3 host, which has a maximum host lattice occupancy by Yb3+ sensitizers, facilitates the utilization of excitation light and enhances energy transfer to activators, resulting in improved UC luminescence. Specifically, by shortening the ionic spacing between sensitizer and activator, the energy back transfer and the cross-relaxation process are promoted, resulting in weakening of green energy level 4S3/2 and 2H11/2 emission and enhancement of red energy level 4F9/2 emission. The prepared Yb2O3: Er TCs exhibited superior optical properties with in-line transmittance over 80% at 600 nm. Notably, in the 980nm-excited UC spectrum, green emission does not appear, thus Yb2O3: Er TCs exhibit ultra-pure single band red emission, with CIE coordinates of (0.72, 0.28) and color purity exceeding 99.9%. To the best of our knowledge, this is the first demonstration of pure red UC luminescence in TCs. Furthermore, the luminescent intensity ratio (LIR) technique was utilized to apply this pure red-emitting TCs for temperature sensing. The absolute sensitivity of Yb2O3: Er TCs was calculated to be 0.319% K-1 at 304 K, which is the highest level of optical thermometry based on 4F9/2 levels splitting of Er3+ known so far. The integration between pure red UC luminescence and temperature sensing performance opens up new possibilities for the development of multi-functional smart windows.

3.
Mol Cell Biochem ; 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37440121

RESUMO

IL-22 serves a protective function in the intestinal barrier. These protective properties of IL-22 may offer a potential treatment for ulcerative colitis (UC). However, the exact mechanisms of action remain unclear. Autophagy plays an important protective role in stabilizing the intestinal barrier. We aimed to explore the role of autophagy in the IL-22-mediated-protective effects in UC. Dextran sulfate sodium (DSS) was administrated via drinking water over 7 days to induce acute UC in BALB/c mice. Treatments with IL-22 (0.25 µg/10 g bodyweight) were started by intraperitoneal injection on days 1, 3, and 5. Weight, disease activity index, histological score, and myeloperoxidase (MPO) activity were used to evaluate the severity of colitis. The expressions of occludin and autophagy-related proteins LC3BII/I were measured by western blot analysis. The lipopolysaccharide-induced HT-29 cell model was used to explore the mechanism. In vivo, IL-22 significantly alleviated DSS-induced clinical manifestations, reduced histological injury, and inhibited MPO activity. IL-22 upregulated the expression of occludin and the LC3B II/I ratio in the colon. In vitro, IL-22 significantly lowered TNF-α levels and enhanced the expression of occludin and the LC3B II/I ratio. Importantly, inhibiting autophagy in vitro by 3-Methyladenine (3-MA) attenuated the occludin protective effects of IL-22. In summary, our findings demonstrate that IL-22 ameliorates DSS-induced ulcerative colitis, which may be attributable to activating autophagy and then promoting occludin expression.

4.
BMC Musculoskelet Disord ; 23(1): 43, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027036

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is widely used for the evaluation of knee injuries, however, the accuracy of MRI in classifying multiple ligament knee injuries (MLKIs) remains unknown. This study aimed to investigate the accuracy of MRI in diagnosing and classifying acute traumatic MLKIs, we hypothesize that MRI had high accuracy in detecting and classifying MLKIs. METHODS: The clinical data of 97 patients who were diagnosed with acute traumatic MLKIs and managed by multi-ligament reconstruction between 2012 and 2020 were retrospectively reviewed. The MR images were read by two experienced radiologists and results were compared with intraoperative findings, which were considered as the reference for the identification of injured structures. The value of MRI in detecting injuries of anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL), and meniscus was evaluated by calculating the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and kappa coefficients analysis. The value of MRI in classifying MLKIs was evaluated by calculating the agreement between MRI and intraoperative findings. RESULTS: For detecting the specific injured structures in MLKIs, MRI had high sensitivity (90.7% for ACL, 90.4% for PCL, and moderate specificity (63.6% for ACL, 50% for PCL) in detecting cruciate ligament injuries, moderate sensitivity (79.1% for MCL, 55.6% for LCL) and specificity (46.7% for MCL, 68.4% for LCL) in detecting collateral ligament injuries, fair sensitivity (61.5%) and low specificity (39.4%) in the diagnosis of injuries to the meniscus. For classifying the MIKIs, MRI had a moderate agreement with intraoperative findings in classifying KD-V (kappa value = 0.57), poor agreement in the KD-I (kappa value = 0.39) and KD-IIIM (kappa value = 0.31), meaningless in the KD-II and KD-IIIL (kappa value < 0). The overall agreement between MRI and intraoperative findings in classifying MLKIs was poor (kappa value = 0.23). CONCLUSIONS: MRI is valuable in early detection and diagnosis of acute MLKIs, however, the accuracy of MRI in classifying MLKIs is limited. The management of MLKIs should be based on intraoperative findings, physical examinations, and comprehensive imaging results.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho , Ligamento Cruzado Posterior , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Lesões do Ligamento Cruzado Anterior/cirurgia , Humanos , Traumatismos do Joelho/diagnóstico por imagem , Traumatismos do Joelho/cirurgia , Imageamento por Ressonância Magnética , Ligamento Cruzado Posterior/diagnóstico por imagem , Ligamento Cruzado Posterior/cirurgia , Estudos Retrospectivos
5.
J Cell Physiol ; 235(4): 3905-3915, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31642074

RESUMO

H3 modification is related to a wide range of tumors, including liver cancer. The Ras passageway is actuated in human diseases. Thus, we investigated the roles of Ras in liver cancer cells via acetylation of H3K56. Ras-carrying G12V and Y40C site mutation was transfected into liver cancer cell lines SNU-475 and SK-Hep-1. Acetylation of H3K56 and phosphatidylinositol 3-kinase (PI3K), P300/CBP-associated factor (PCAF) and Mouse double minute 2 homolog (MDM2) was tested via western blot. Cell activity, colonies, and migration were tested via Cell Counting Kit-8, soft-agar colony formation, and Transwell experiment, respectively. Sirtuin 6 (SIRT6) and PCAF were tested via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Chromatin immunoprecipitation was employed to test the relationship between Ras and downstream elements. Flow cytometry was employed to test cell cycle series. We found that RasG12V/Y40C transfection reduced the acetylation of H3K56 and activated phosphorylation of protein kinase B. H3K56Q (H3K56ac overexpression) suppressed cell activity, colonies, and migration. H3K56ac changed Ras downstream factors expression. RasG12V/Y40C bound to Ras-PI3K downstream elements' promoters. SIRT6 silencing raised H3K56ac and suppressed cell activity, migration and S phage cell percentage. SIRT6 silence transformed expression of downstream elements. PCAF and H3K56ac demonstrated the close current while MDM2 was conversed. In summary, the Ras-PI3K passageway promoted cell growth and metastasis via decreasing H3K56ac, in which MDM2-mediated PCAF was involved.


Assuntos
Neoplasias Hepáticas/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Sirtuínas/genética , Fatores de Transcrição de p300-CBP/genética , Acetilação , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Código das Histonas/genética , Histonas/genética , Humanos , Neoplasias Hepáticas/patologia , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais/genética
6.
Pediatr Neurosurg ; 55(4): 188-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33040067

RESUMO

INTRODUCTION: White matter injury (WMI) is the most common brain injury in preterm infants and can result in life-long neurological deficits. The main cause of WMI is damage to the oligodendrocyte precursor cells (OPC) in the brain that results in delayed myelin sheath formation, or the destruction of existing myelin sheaths. OPC undergo highly regulated and strictly timed developmental changes that result in their transformation to mature oligodendrocytes capable of myelin production. OBJECTIVE: Studies have shown that clobetasol strongly promotes differentiation of OPC into myelin sheaths. Therefore, we hypothesized that clobetasol may be a therapeutic option for the treatment of preterm WMI. METHODS: We induced a WMI rat model and observed white matter damage under an optical microscope. Rats subjected to WMI were injected intraperitoneally with clobetasol (2 or 5 mg/kg daily) from day 1 to day 5 in the early treatment groups, or from day 6 to day 10 in the late treatment groups. After 17 days, the rats were sacrificed and the expression of myelin basic protein (MBP) was visualized using immunofluorescence. In addition, we evaluated myelin sheath formation using electron microscopy. The rats were also subjected to the suspension test, ramp test, and open field test to evaluate neurobehavioral functions. RESULTS: A rat model of WMI was successfully induced. It was found that clobetasol significantly induced MBP expression and myelin sheath formation and improved neurobehavioral function in the rats subjected to WMI. CONCLUSIONS: Our results indicate that clobetasol attenuates WMI by promoting OPC differentiation, and it may be an effective therapeutic agent for the treatment of preterm WMI.


Assuntos
Lesões Encefálicas , Células Precursoras de Oligodendrócitos , Substância Branca , Animais , Animais Recém-Nascidos , Diferenciação Celular , Clobetasol , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Bainha de Mielina , Oligodendroglia , Ratos
7.
Biochem Biophys Res Commun ; 519(4): 697-704, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31542234

RESUMO

At present, whether α2-adrenoceptors in the prelimbic cortex (PrL) are involved in Parkinson's disease-related anxiety is unclear. We examined the effects of PrL α2-adrenoceptors on anxiety-like behaviors in rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. Compared to the sham operation, the lesion induced anxiety-like responses as measured by the open field test and elevated plus-maze test. Intra-PrL injection of the α2-adrenoceptor agonist clonidine (1.25, 2.5 or 5 µg/rat) produced anxiolytic effects in sham-operated and lesioned rats. Furthermore, intra-PrL injection of the α2-adrenoceptor antagonist idazoxan (1, 2 or 4 µg/rat) induced anxiogenic effects in two groups of rats. The effective doses produced by clonidine and idazoxan in lesioned rats were higher than those in sham-operated rats. Neurochemical results showed that intra-PrL injection of clonidine (5 µg/rat) or idazoxan (4 µg/rat) decreased or increased dopamine (DA) and noradrenaline (NA) and serotonin (5-HT) levels in the medial prefrontal cortex (mPFC) and amygdala in sham-operated and lesioned rats, respectively. These results suggest that α2-adrenoceptors in the PrL are involved in the regulation of anxiety-like behaviors, which is attributable to changes in DA, NA and 5-HT levels in the mPFC and amygdala after activation and blockade of α2-adrenoceptors.


Assuntos
Ansiedade/metabolismo , Sistema Límbico/metabolismo , Transtornos Parkinsonianos/metabolismo , Córtex Pré-Frontal/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/fisiopatologia , Aminas Biogênicas/metabolismo , Clonidina/farmacologia , Idazoxano/farmacologia , Sistema Límbico/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos Parkinsonianos/fisiopatologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos Sprague-Dawley
8.
Opt Lett ; 44(17): 4139-4142, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465348

RESUMO

We study terahertz (THz) optoelectronic properties of monolayer (ML) MoS2 placed on different substrates such as SiO2/Si, sapphire, and quartz. Through the measurements of THz Fourier transform spectroscopy (2.5-6.5 THz) and THz time-domain spectroscopy (TDS, 0.2-1.2 THz), we find that the real part of optical conductivity increases for ML MoS2 on SiO2/Si and sapphire substrates and decreases for it on quartz with increasing radiation frequency. It is shown that the complex optical conductivity for ML MoS2, obtained from THz TDS measurements, can fit very well to the Drude-Smith formula. Thus, the dependence of optical conductivity of ML MoS2 on different substrates can be understood via a mechanism of electronic localization, and the electron density, relaxation time, and localization factor of the sample can be determined optically. Furthermore, we examine the influence of temperature on these key parameters in ML MoS2 on different substrates. The results obtained from this Letter indicate that THz spectroscopy is a very powerful tool in studying and characterizing ML MoS2-based electronic systems, especially in examining the electronic localization effect which cannot be directly measured in conventional electrical transport experiment. This Letter is relevant to an in-depth understanding of the optoelectronic properties of ML MoS2 and of the proximity effect induced by different substrates.

9.
Chemistry ; 25(45): 10561-10565, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31125477

RESUMO

Developing simple and cost-efficient methods for fabricating molecular patterns is of great importance in the field of nanoscience and nanotechnology. Here, a simple and convenient method was developed for fabricating nanopatterns composed of positively charged silane molecules by using silver nanowires as templates. The as-obtained silane pattern copies the shape of the silver nanowires and is only 0.7 nm thick, which can later be used for templated assembly of small molecules and nanoparticles of opposite charges. As a proof of concept, the resultant assembly could be further used for surface-enhanced Raman scattering.

10.
J Phys D Appl Phys ; 51(44): 443001, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30799880

RESUMO

Developments in microscopy have been instrumental to progress in the life sciences, and many new techniques have been introduced and led to new discoveries throughout the last century. A wide and diverse range of methodologies is now available, including electron microscopy, atomic force microscopy, magnetic resonance imaging, small-angle x-ray scattering and multiple super-resolution fluorescence techniques, and each of these methods provides valuable read-outs to meet the demands set by the samples under study. Yet, the investigation of cell development requires a multi-parametric approach to address both the structure and spatio-temporal organization of organelles, and also the transduction of chemical signals and forces involved in cell-cell interactions. Although the microscopy technologies for observing each of these characteristics are well developed, none of them can offer read-out of all characteristics simultaneously, which limits the information content of a measurement. For example, while electron microscopy is able to disclose the structural layout of cells and the macromolecular arrangement of proteins, it cannot directly follow dynamics in living cells. The latter can be achieved with fluorescence microscopy which, however, requires labelling and lacks spatial resolution. A remedy is to combine and correlate different readouts from the same specimen, which opens new avenues to understand structure-function relations in biomedical research. At the same time, such correlative approaches pose new challenges concerning sample preparation, instrument stability, region of interest retrieval, and data analysis. Because the field of correlative microscopy is relatively young, the capabilities of the various approaches have yet to be fully explored, and uncertainties remain when considering the best choice of strategy and workflow for the correlative experiment. With this in mind, the Journal of Physics D: Applied Physics presents a special roadmap on the correlative microscopy techniques, giving a comprehensive overview from various leading scientists in this field, via a collection of multiple short viewpoints.

11.
Phys Chem Chem Phys ; 17(33): 21127-32, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-25201467

RESUMO

Fluorescence correlation spectroscopy (FCS) is a standard tool for studying diffusion of molecules in solution, but is limited to low analyte concentrations, in the range between 10 pM and 1 nM. Such concentration limitations can be overcome by using a plasmonic nanoantenna which confines the electric field of excitation light into a tiny volume near its surface and thereby reduces the effective excitation volume by several orders of magnitude. Here we demonstrate successful FCS measurements on a 1 µM solution of crystal violet (CV) dye in glycerol using a gold nanorod antenna. Our correlation analysis yields two components: (i) a slow component with correlation time of about 100 ms, which is attributed to sticking and bleaching of the dye, and (ii) a fast component of about 1 ms, which could arise from dye diffusion through the near-field of the nanorod and/or from blinking due to intersystem crossing or photochemistry.

12.
Phys Chem Chem Phys ; 17(9): 6532-44, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25659944

RESUMO

Our previous temperature-cycle study reported FRET transitions between different states on FRET-labeled polyprolines [Yuan et al., PCCP, 2011, 13, 1762]. The conformational origin of such transitions, however, was left open. In this work, we apply temperature-cycle microscopy of single FRET-labeled polyproline and dsDNA molecules and compare their responses to resolve the conformational origin of different FRET states. We observe different steady-state FRET distributions and different temperature-cycle responses in the two samples. Our temperature-cycle results on single molecules resemble the results in steady-state measurements but reveal a dark state which could not be observed otherwise. By comparing the timescales and probabilities of different FRET states in temperature-cycle traces, we assign the conformational heterogeneity reflected by different FRET states to linker dynamics, dye-chain and dye-dye interactions. The dark state and low-FRET state are likely due to dye-dye interactions at short separations.


Assuntos
Microscopia/métodos , Conformação Molecular , Temperatura , Transferência Ressonante de Energia de Fluorescência
13.
Exp Ther Med ; 27(1): 31, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38125359

RESUMO

ß-Amyloid peptide (Aß) deposition in the brain is an important pathological change in Alzheimer's disease (AD). Insulin-degrading enzyme (IDE), which is regulated transcriptionally by peroxisome proliferator-activated receptor γ (PPARγ), is able to proteolyze Aß. One of the members of the MAPK family, ERK, is able to mediate the phosphorylation of PPARγ at Ser112, thereby inhibiting its transcriptional activity. Ginsenoside Rg1 is one of the active ingredients in the natural medicine ginseng and has inhibitory effects on Aß production. The present study was designed to investigate whether ginsenoside Rg1 is able to affect the regulation of PPARγ based on the expression of its target gene, IDE, and whether it is able to promote Aß degradation via inhibition of the ERK/PPARγ phosphorylation pathway. In the present study, primary cultured rat hippocampal neurons were treated with Aß1-42, ginsenoside Rg1 and the ERK inhibitor PD98059, and subsequently TUNEL staining was used to detect the level of neuronal apoptosis. ELISA was subsequently employed to detect the intra- and extracellular Aß1-42 levels, immunofluorescence staining and western blotting were used to detect the translocation of ERK from the cytoplasm to the nucleus, immunofluorescence double staining was used to detect the co-expression of ERK and PPARγ, and finally, western blotting was used to detect the phosphorylation of PPARγ at Ser112 and IDE expression. The results demonstrated that ginsenoside Rg1 or PD98059 were able to inhibit primary cultured hippocampal neuron apoptosis induced by Aß1-42 treatment, reduce the levels of intra- and extraneuronal Aß1-42 and inhibit the translocation of ERK from the cytoplasm to the nucleus. Furthermore, administration of ginsenoside Rg1 or PD98059 resulted in attenuated co-expression of ERK and PPARγ, inhibition of phosphorylation of PPARγ at Ser112 mediated by ERK and an increase in IDE expression. In addition, the effects when PD98059 to inhibit ERK followed by treatment with ginsenoside Rg1 were found to be more pronounced than those when using PD98059 alone. In conclusion, ginsenoside Rg1 was demonstrated to exert neuroprotective effects on AD via inhibition of the ERK/PPARγ phosphorylation pathway, which led to an increase in IDE expression, the promotion of Aß degradation and the decrease of neuronal apoptosis. These results could provide a theoretical basis for the clinical application of ginsenoside Rg1 in AD.

14.
Arch Osteoporos ; 19(1): 38, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750277

RESUMO

Data from English randomized controlled trials comparing unilateral versus bilateral PKP for the treatment of OVCFs were retrieved and analyzed, and the results showed that unilateral PKP is a better choice for the treatment of patients with OVCFs, which will provide a reliable clinical rationale for the treatment of OVCFs. PURPOSE: To investigate the advantages of unilateral percutaneous kyphoplasty (PKP) for the treatment of osteoporotic vertebral compression fractures(OVCFs). METHODS: The systematic evaluation program met all program requirements (CRD 42023422383) by successfully passing the PROSPERO International Prospective Systematic Evaluation Registry. Researchers searched the references of English-language randomized controlled trials comparing unilateral and bilateral PKP for the treatment of osteoporotic vertebral compression fractures published between 2010 and 2023 and manually searched for known primary and review articles. The study statistically analyzed data from all the included literature, which primarily included time to surgery, visual pain score(VAS) and Oswestry disability index(ODI) at postoperative follow-up time points, polymethylmethacrylate (PMMA, bone cement) injection dose, cement leakage, radiation dose, and improvement in kyphotic angle. RESULTS: This meta-analysis searched 416 articles published from 2010 to 2023 based on keywords, and 18 articles were finally included in this study. The results of the forest plot showed that unilateral PKP operative time, amount of bone cement used, and radiation dose to the patient were significantly reduced (p < 0.01, p < 0.01, and p < 0.01, respectively), and unilateral and bilateral PKP had comparable cement leakage (p = 0.49, 95% CI = 0.58-1.30), and there was no significant difference in the kyphotic angle between unilateral and bilateral PKP (p = 0.42, 95% CI = - 2.29-0.96). During follow-up, there was no significant difference in pain relief between unilateral and bilateral PKP (p = 0.70, 95% CI = - 0.09-0.06), nor was there a significant difference in ODI (p = 0.27, 95% CI = - 0.35-1.24). CONCLUSIONS: There is no difference in clinical efficacy between unilateral PKP and bilateral PKP, but unilateral PKP has a shorter operative time, a lower incidence of cement leakage, a lower amount of cement, and a lower radiation dose to the patient and operator. Unilateral PKP is a better option for patients with OVCFs.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Cifoplastia/métodos , Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Cimentos Ósseos/uso terapêutico , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Adv Mater ; 36(5): e2305375, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930270

RESUMO

Maximizing atom-utilization efficiency and high current stability are crucial for the platinum (Pt)-based electrocatalysts for hydrogen evolution reaction (HER). Herein, the Pt single-atom anchored molybdenum (Mo) foil (Pt-SA/Mo-L) as a single-atom alloy electrode is synthesized by the laser ablation strategy. The local thermal effect with fast rising-cooling rate of laser can achieve the single-atom distribution of the precious metals (e.g., Pt, Rh, Ir, and Ru) onto the Mo foil. The synthesized self-standing Pt-SA/Mo-L electrode exhibits splendid catalytic activity (31 mV at 10 mA cm-2 ) and high-current-density stability (≈850 mA cm-2 for 50 h) for HER in acidic media. The strong coordination of Pt-Mo bonding in Pt-SA/Mo-L is critical for the efficient and stable HER. In addition, the ultralow electrolytic voltage of 0.598 V to afford the current density of 50 mA cm-2 is realized by utilization of the anodic molybdenum oxidation instead of the oxygen evolution reaction (OER). Here a universal synthetic strategy of single-atom alloys (PtMo, RhMo, IrMo, and RuMo) as self-standing electrodes is provided for ultralow voltage and membrane-free hydrogen production.

16.
ACS Appl Mater Interfaces ; 16(22): 28526-28536, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775170

RESUMO

NiFe layered double hydroxide (LDH) with abundant heterostructures represents a state-of-the-art electrocatalyst for the alkaline oxygen evolution reaction (OER). Herein, NiFe LDH/Fe2O3 nanosheet arrays have been fabricated by facile combustion of corrosion-engineered NiFe foam (NFF). The in situ grown, self-supported electrocatalyst exhibited a low overpotential of 248 mV for the OER at 50 mA cm-2, a small Tafel slope of 31 mV dec-1, and excellent durability over 100 h under the industrial benchmarking 500 mA cm-2 current density. A balanced Ni and Fe composition under optimal corrosion and combustion contributed to the desirable electrochemical properties. Comprehensive ex-situ analyses and operando characterizations including Fourier-transformed alternating current voltammetry (FTACV) and in situ Raman demonstrate the beneficial role of modulated interfacial electron transfer, dynamic atomic structural transformation to NiOOH, and the high-valence active metal sites. This study provides a low-cost and easy-to-expand way to synthesize efficient and durable electrocatalysts.

17.
Adv Sci (Weinh) ; 11(13): e2304349, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38243637

RESUMO

Cost-effective non-noble metal-based catalysts for selective hydrogenation with excellent activity, selectivity, and durability are still the holy grail. Herein, an oxygen-doped carbon (OC) chainmail encapsulated dilute Cu-Ni alloy is developed by simple pyrolysis of Cu/Ni-metal-organic framework. The CuNi0.05@OC catalyst displays superior performance for atmospheric pressure transfer hydrogenation of p-chloronitrobenzene and p-nitrophenol, and for hydrogenation of furfural, all in water and with exceptional durability. Comprehensive characterizations confirm the close interactions between the diluted Ni sites, the base Cu, and optimized three-layered graphene chainmail. Theoretical calculations demonstrate that the properly tuned lattice strain and Schottky junction can adjust electron density to facilitate specific adsorption on the active centers, thus enhancing the catalytic activity and selectivity, while the OC shell also offers robust protection. This work provides a simple and environmentally friendly strategy for developing practical heterogeneous catalysts that bring the synergistic effect into play between dilute alloy and functional carbon wrapping.

18.
J Orthop Surg Res ; 18(1): 916, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041147

RESUMO

BACKGROUND: Intervertebral disc degeneration (IDD) is the main pathogenesis of low back pain. MicroRNAs (miRNAs) have been found to exert regulatory function in IDD. This study aimed to investigate the effect and potential mechanism of miR-96-5p in IDD. METHODS: In vitro cell model of IDD was established by treating human nucleus pulposus cells (HNPCs) with interleukin-1ß (IL-1ß). The level of peroxisome proliferator-activated receptor γ (PPARγ) was examined in the IDD cell model by Western blot and quantification real-time reverse transcription-polymerase chain reaction (qRT-PCR). The expression level of miR-96-5p was detected by RT-qPCR. Effects of PPARγ or/and PPARγ agonist on inflammatory factors, extracellular matrix (ECM), apoptosis, and nuclear factor-kappaB (NF-κB) nuclear translocation were examined through enzyme-linked immunosorbent assay (ELISA), Western blot, flow cytometry assay, and immunofluorescence staining. The Starbase database and dual luciferase reporter assay were used to predict and validate the targeting relationship between miR-96-5p and PPARγ, and rescue assay was performed to gain insight into the role of miR-96-5p on IDD through PPARγ/NF-κB signaling. RESULTS: PPARγ expression reduced with concentration and time under IL-1ß stimulation, while miR-96-5p expression showed the reverse trend (P < 0.05). Upregulation or/and activation of PPARγ inhibited IL-1ß-induced the increase in inflammatory factor levels, apoptosis, degradation of the ECM, and the nuclear translocation of NF-κB (P < 0.05). MiR-96-5p was highly expressed but PPARγ was lowly expressed in IDD, while knockdown of PPARγ partially reversed remission of IDD induced by miR-96-5p downregulation (P < 0.05). MiR-96-5p promoted NF-κB entry into the nucleus but PPARγ inhibited this process. CONCLUSION: Inhibition of miR-96-5p suppressed IDD progression by regulating the PPARγ/NF-κB pathway. MiR-96-5p may be a promising target for IDD treatment clinically.


Assuntos
Degeneração do Disco Intervertebral , MicroRNAs , Humanos , NF-kappa B/metabolismo , Degeneração do Disco Intervertebral/patologia , PPAR gama/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação para Baixo , Apoptose/genética
19.
Spine (Phila Pa 1976) ; 48(18): E317-E328, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37384872

RESUMO

STUDY DESIGN: Basic science laboratory study. OBJECTIVE: To identify hub genes related to bone morphogenetic proteins (BMPs) in the ossification of the ligamentum flavum (OLF) and analyze their functional characteristics. SUMMARY OF BACKGROUND DATA: The exact etiology and pathologic mechanism of OLF remain unclear. BMPs are pleiotropic osteoinductive proteins that may play a critical role in this condition. MATERIALS AND METHODS: The GSE106253 and GSE106256 data sets were downloaded from the Gene Expression Omnibus database. The messenger RNA (mRNA) and long noncoding RNA expression profiles were obtained from GSE106253. The microRNA expression profiles were obtained from GSE106256. Differentially expressed genes were identified between OLF and non-OLF groups and then intersected with BMP-related genes to obtain differentially expressed BMP-related genes. The least absolute shrinkage selection operator and support vector machine recursive feature elimination were used to screen hub genes. Furthermore, a competing endogenous RNA network was constructed to explain the expression regulation of the hub genes in OLF. Finally, the protein and mRNA expression levels of the hub genes were verified using Western blot and real-time polymerase chain reaction, respectively. RESULTS: We identified 671 Differentially expressed genes and 32 differentially expressed BMP-related genes. Hub genes ADIPOQ , SCD , SCX , RPS18 , WDR82 , and SPON1 , identified through the least absolute shrinkage selection operator and support vector machine recursive feature elimination analyses, showed high diagnostic values for OLF. Furthermore, the competing endogenous RNA network revealed the regulatory mechanisms of the hub genes. Real-time polymerase chain reaction showed that the mRNA expression of the hub genes was significantly downregulated in the OLF group compared with the non-OLF group. Western blot showed that the protein levels of ADIPOQ, SCD, WDR82 , and SPON1 were significantly downregulated, whereas those of SCX and RPS18 were significantly upregulated in the OLF group compared with the non-OLF group. CONCLUSION: This study is the first to identify BMP-related genes in OLF pathogenesis through bioinformatics analysis. ADIPOQ , SCD , SCX , RPS18 , WDR82 , and SPON1 were identified as hub genes for OLF. The identified genes may serve as potential therapeutic targets for treating patients with OLF.


Assuntos
Ligamento Amarelo , Osteogênese , Humanos , Osteogênese/genética , Ligamento Amarelo/patologia , Redes Reguladoras de Genes , Proteínas Morfogenéticas Ósseas/genética , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo
20.
Biochem Biophys Res Commun ; 425(4): 735-40, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22885180

RESUMO

Lectin-like oxidized low-density lipoprotein (oxLDL) receptor-1 (LOX-1) was originally identified as a receptor for oxLDL predominantly expressed in endothelial cells. Recently up-regulation of LOX-1 has been implicated in oxidative stress and cell apoptosis in many cell types. However, LOX-1 expression in neurons or regulation of neuronal apoptosis by LOX-1 has not been reported. To investigate the possible roles of LOX-1 in hypertension induced brain damage, we examined the distribution of LOX-1 in cortex and hippocampus and compared its expression in 32-week-old SHR and WKY rats. Immunofluorescence revealed that LOX-1 positive cells were located principally at the cortex involved in sensory information processing and were mainly expressed in neurons. We also found up-regulated mRNA expression of LOX-1, Bax and caspase-3 and down-regulated mRNA expression of Bcl-2 in SHR group. Compared with WKY group, SHR group showed increased LOX-1 positive cells and TUNEL positive cells. Furthermore, double-labeling method indicated that LOX-1 expression was colocalized with TUNEL positive cells, which means that LOX-1 expression was involved in hypertension related cell apoptosis. These findings indicated that LOX-1 expression was up-regulated in the cortex of SHR and its expression has implication in neuronal apoptosis. Elevated Bax/Bcl-2 ratio may be involved under this event.


Assuntos
Apoptose , Córtex Cerebral/patologia , Hipertensão/patologia , Neurônios/patologia , Receptores Depuradores Classe E/metabolismo , Animais , Córtex Cerebral/metabolismo , Hipertensão/metabolismo , Masculino , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Proteína X Associada a bcl-2/biossíntese
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