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1.
J Am Chem Soc ; 146(15): 10934-10942, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38581437

RESUMO

Hydroxylamine (HA, NH2OH) is a critical feedstock in the production of various chemicals and materials, and its efficient and sustainable synthesis is of great importance. Electroreduction of nitrate on Cu-based catalysts has emerged as a promising approach for green ammonia (NH3) production, but the electrosynthesis of HA remains challenging due to overreduction of HA to NH3. Herein, we report the first work on ketone-mediated HA synthesis using nitrate in water. A metal-organic-framework-derived Cu catalyst was developed to catalyze the reaction. Cyclopentanone (CP) was used to capture HA in situ to form CP oxime (CP-O) with C═N bonds, which is prone to hydrolysis. HA could be released easily after electrolysis, and CP was regenerated. It was demonstrated that CP-O could be formed with an excellent Faradaic efficiency of 47.8%, a corresponding formation rate of 34.9 mg h-1 cm-2, and a remarkable carbon selectivity of >99.9%. The hydrolysis of CP-O to release HA and CP regeneration was also optimized, resulting in 96.1 mmol L-1 of HA stabilized in the solution, which was significantly higher than direct nitrate reduction. Detailed in situ characterizations, control experiments, and theoretical calculations revealed the catalyst surface reconstruction and reaction mechanism, which showed that the coexistence of Cu0 and Cu+ facilitated the protonation and reduction of *NO2 and *NH2OH desorption, leading to the enhancement for HA production.

2.
Small ; : e2403099, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973084

RESUMO

Bottom-up patterning technology plays a significant role in both nature and synthetic materials, owing to its inherent advantages such as ease of implementation, spontaneity, and noncontact attributes, etc. However, constrained by the uncontrollability of molecular movement, energy interaction, and stress, obtained micropatterns tend to exhibit an inevitable arched outline, resulting in the limitation of applicability. Herein, inspired by auxin's action mode in apical dominance, a versatile strategy is proposed for fabricating precision self-organizing micropatterns with impressive height based on polymerization-induced acropetal migration. The copolymer containing fluorocarbon chains (low surface energy) and tertiary amine (coinitiator) is designed to self-assemble on the surface of the photo-curing system. The selective exposure under a photomask establishes a photocuring boundary and the radicals would be generated on the surface, which is pivotal in generating a vertical concentration difference of monomer. Subsequent heating treatment activates the material continuously transfers from the unexposed area to the exposed area and is accompanied by the obviously vertical upward mass transfer, resulting in the manufacture of a rectilinear profile micropattern. This strategy significantly broadens the applicability of self-organizing patterns, offering the potential to mitigate the complexity and time-consuming limitations associated with top-down methods.

3.
Eur Radiol ; 34(4): 2759-2771, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37736802

RESUMO

OBJECTIVES: A decline in language function is a common complication after glioma surgery, affecting patients' quality of life and survival. This study predicts the postoperative decline in language function and whether it can be recovered based on the preoperative white matter structural network. MATERIALS AND METHODS: Eighty-one right-handed patients with glioma involving the left hemisphere were retrospectively included. Their language function was assessed using the Western Aphasia Battery before and 1 week and 3 months after surgery. Structural connectome combining DTI features was selected to predict postoperative language decline and recovery. Nested cross-validation was used to optimize the models, evaluate the prediction performance of the models, and identify the most predictive features. RESULTS: Five, seven, and seven features were finally selected as the predictive features in each model and used to establish predictive models for postoperative language decline (1 week after surgery), long-term language decline (3 months after surgery), and language recovery, respectively. The overall accuracy of the three models in nested cross-validation and overall area under the receiver operating characteristic curve were 0.840, 0.790, and 0.867, and 0.841, 0.778, and 0.901, respectively. CONCLUSION: We used machine learning algorithms to establish models to predict whether the language function of glioma patients will decline after surgery and whether postoperative language deficit can recover, which may help improve the development of treatment strategies. The difference in features in the non-language decline or the language recovery group may reflect the structural basis for the protection and compensation of language function in gliomas. CLINICAL RELEVANCE STATEMENT: Models can predict the postoperative language decline and whether it can recover in glioma patients, possibly improving the development of treatment strategies. The difference in selected features may reflect the structural basis for the protection and compensation of language function. KEY POINTS: • Structural connectome combining diffusion tensor imaging features predicted glioma patients' language decline after surgery. • Structural connectome combining diffusion tensor imaging features predicted language recovery of glioma patients with postoperative language disorder. • Diffusion tensor imaging and connectome features related to language function changes imply plastic brain regions and connections.


Assuntos
Neoplasias Encefálicas , Conectoma , Glioma , Humanos , Imagem de Tensor de Difusão/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Estudos Retrospectivos , Qualidade de Vida , Glioma/diagnóstico por imagem , Glioma/cirurgia
4.
Eur Radiol ; 34(2): 1349-1357, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37581664

RESUMO

OBJECTIVES: To investigate the association between spinal cord perfusion and microstructural damage in CSM patients who underwent cervical laminoplasty using MR dynamic susceptibility contrast (DSC), diffusion tensor imaging (DTI), and neurite orientation dispersion and density imaging (NODDI) techniques. METHODS: A follow-up cohort study was conducted with 53 consecutively recruited CSM patients who had undergone cervical laminoplasty 12-14 months after the surgery from April 2016 to December 2016. Twenty-one aged-matched healthy volunteers were recruited as controls. For each patient, decompressed spinal cord levels were imaged on a 3.0-T MRI scanner by diffusion and DSC sequences to quantify the degrees of microstructural damage and perfusion conditions, respectively. The diffusion data were analyzed by DTI and NODDI models to produce diffusion metrics. Classic indicator dilution model was used to quantify the DSC metrics. Mann-Whitney U test was performed for comparison of diffusion metrics between patients and healthy controls. Pearson correlation was used to explore the associations between the metrics of spinal cord perfusion and microstructural damage. RESULTS: DTI metrics, neurite density, and isotropic volume fraction had significant differences between postoperative patients and healthy controls. Pearson correlation test showed that SCBV was significantly positively correlated with RD, MD, and ODI, and negatively correlated with FA and NDI. SCBF was found to be significantly positively correlated with RD and MD, and negatively correlated with FA. CONCLUSIONS: Increased spinal cord perfusion quantified by DSC is associated with microstructural damage assessed by diffusion MRI in CSM patients who underwent cervical laminoplasty. CLINICAL RELEVANCE STATEMENT: This study found that the spinal cord perfusion is associated with microstructural damage in postoperative cervical spondylotic myelopathy patients, indicating that high perfusion may play a role in the pathophysiological process of cervical spondylotic myelopathy and deserves more attention. KEY POINTS: • Spinal cord microstructural damage can be persistent despite the compression had been relieved 12-14 months after the cervical laminoplasty in cervical spondylotic myelopathy (CSM) patients. • Spinal cord perfusion is associated with microstructural damage in CSM patients after the cervical laminoplasty. • Inflammation in the decompressed spinal cord may be a cause of increased perfusion and is associated with microstructural damage during the recovery period of CSM.


Assuntos
Laminoplastia , Doenças da Medula Espinal , Espondilose , Humanos , Idoso , Imagem de Tensor de Difusão/métodos , Seguimentos , Laminoplastia/efeitos adversos , Espondilose/complicações , Espondilose/diagnóstico por imagem , Espondilose/cirurgia , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/cirurgia , Doenças da Medula Espinal/complicações , Medula Espinal , Vértebras Cervicais/cirurgia , Perfusão
5.
J Nat Prod ; 87(6): 1643-1651, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38848113

RESUMO

Five cyclopenta[d]pyrano[4,3-b]pyran-1,7(6H)-dione 6/6/5-fused tricyclic ring system containing metabolites peniapyrones A-E (1-5), and four previously undescribed cyclopenta[4,5]furo[3,2-c]pyran-1-one 6/5/5-fused tricyclic ring system containing compounds peniapyrones F-I (6-9), were isolated from the endophytic Penicillium brefeldianum F4a. Their structures, including absolute configurations, were determined through spectroscopic analysis and quantum chemical calculations. Peniapyrones D (4) and E (5) were a pair of diastereoisomers. Compounds 1, 3, and 5-9 showed cytotoxic activity against AsPC-1, CRL-2234, and MCF-7 cancer cell lines. Compounds 1, 3, 6, 8, and 9 inhibited the Kirsten rat sarcoma viral oncogene homologue (KRAS) mutant AsPC-1 cell line.


Assuntos
Penicillium , Pironas , Pironas/química , Pironas/farmacologia , Pironas/isolamento & purificação , Penicillium/química , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
6.
J Nanobiotechnology ; 22(1): 34, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238748

RESUMO

Severe tissue injuries pose a significant risk to human health. Conventional wound dressings fall short in achieving effective tissue regeneration, resulting in suboptimal postoperative healing outcomes. In this study, an asymmetric adhesive wound dressing (marked as SIS/PAA/LAP) was developed, originating from acrylate acid (AA) solution with laponite (LAP) nanoparticles polymerization and photo-crosslinked on the decellularized extracellular matrix small intestinal submucosa (SIS) patch. Extensive studies demonstrated that the SIS/PAA/LAP exhibited higher tissue adhesion strength (~ 33 kPa) and burst strength (~ 22 kPa) compared to conventional wound dressings like Tegaderm and tissue adhesive products. Importantly, it maintained favorable cell viability and demonstrated robust angiogenic capacity. In animal models of full-thickness skin injuries in rats and skin injuries in Bama miniature pigs, the SIS/PAA/LAP could be precisely applied to wound sites. By accelerating the formation of tissue vascularization, it displayed superior tissue repair outcomes. This asymmetrically adhesive SIS-based patch would hold promising applications in the field of wound dressings.


Assuntos
Adesivos , Cicatrização , Humanos , Ratos , Animais , Suínos , Adesivos/farmacologia , Pele , Bandagens
7.
Clin Exp Pharmacol Physiol ; 51(8): e13904, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923060

RESUMO

Myocardial ischemia-reperfusion injury (MIRI) is a common clinic scenario that occurs in the context of reperfusion therapy for acute myocardial infarction. It has been shown that cocaine and amphetamine-regulated transcript (CART) can ameliorate cerebral ischemia-reperfusion (I/R) injury, but the effect of CART on MIRI has not been studied yet. Here, we revealed that CART protected the heart during I/R process by inhibiting apoptosis and excessive autophagy, indicating that CART would be a potential drug candidate for the treatment of MIRI. Further analysis showed that CART upregulated the activation of phospho-AKT, leading to downregulation of lactate dehydrogenase (LDH) release, apoptosis, oxidative stress and excessive autophagy after I/R, which was inhibited by PI3K inhibitor, LY294002. Collectively, CART attenuated MIRI through inhibition of cardiomyocytes apoptosis and excessive autophagy, and the protective effect was dependent on PI3K/AKT signalling pathway.


Assuntos
Apoptose , Autofagia , Traumatismo por Reperfusão Miocárdica , Proteínas do Tecido Nervoso , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Apoptose/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Masculino , Autofagia/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley
8.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34810249

RESUMO

Camouflage is widespread in nature, engineering, and the military. Dynamic surface wrinkles enable a material the on-demand control of the reflected optical signal and may provide an alternative to achieve adaptive camouflage. Here, we demonstrate a feasible strategy for adaptive visible camouflage based on light-driven dynamic surface wrinkles using a bilayer system comprising an anthracene-containing copolymer (PAN) and pigment-containing poly (dimethylsiloxane) (pigment-PDMS). In this system, the photothermal effect-induced thermal expansion of pigment-PDMS could eliminate the wrinkles. The multiwavelength light-driven dynamic surface wrinkles could tune the scattering of light and the visibility of the PAN film interference color. Consequently, the color captured by the observer could switch between the exposure state that is distinguished from the background and the camouflage state that is similar to the surroundings. The bilayer wrinkling system toward adaptive visible camouflage is simple to configure, easy to operate, versatile, and exhibits in situ dynamic characteristics without any external sensors and extra stimuli.

9.
J Am Chem Soc ; 145(40): 21945-21954, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37751566

RESUMO

Cu-based electrocatalysts have great potential for facilitating CO2 reduction to produce energy-intensive fuels and chemicals. However, it remains challenging to obtain high product selectivity due to the inevitable strong competition among various pathways. Here, we propose a strategy to regulate the adsorption of oxygen-associated active species on Cu by introducing an oxophilic metal, which can effectively improve the selectivity of C2+ alcohols. Theoretical calculations manifested that doping of Lewis acid metal Al into Cu can affect the C-O bond and Cu-C bond breaking toward the selectively determining intermediate (shared by ethanol and ethylene), thus prioritizing the ethanol pathway. Experimentally, the Al-doped Cu catalyst exhibited an outstanding C2+ Faradaic efficiency (FE) of 84.5% with remarkable stability. In particular, the C2+ alcohol FE could reach 55.2% with a partial current density of 354.2 mA cm-2 and a formation rate of 1066.8 µmol cm-2 h-1. A detailed experimental study revealed that Al doping improved the adsorption strength of active oxygen species on the Cu surface and stabilized the key intermediate *OC2H5, leading to high selectivity toward ethanol. Further investigation showed that this strategy could also be extended to other Lewis acid metals.

10.
Magn Reson Med ; 90(1): 133-149, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36883748

RESUMO

PURPOSE: To compare the performances of uniform-density spiral (UDS), variable-density spiral (VDS), and dual-density spiral (DDS) samplings in multi-shot diffusion imaging, and determine a sampling strategy that balances reliability of shot navigator and overall DWI image quality. THEORY AND METHODS: UDS, VDS, and DDS trajectories were implemented to achieve four-shot diffusion-weighted spiral imaging. First, the static B0 off-resonance effects in UDS, VDS, and DDS acquisitions were analyzed based on a signal model. Then, in vivo experiments were performed to verify the theoretical analyses, and fractional anisotropy (FA) fitting residuals were used to quantitatively assess the quality of spiral diffusion data for tensor estimation. Finally, the SNR performances and g-factor behavior of the three spiral samplings were evaluated using a Monte Carlo-based pseudo multiple replica method. RESULTS: Among the three spiral trajectories with the same readout duration, UDS sampling exhibited the least off-resonance artifacts. This was most evident when the static B0 off-resonance effect was severe. The UDS diffusion images had higher anatomical fidelity and lower FA fitting residuals than the other two counterparts. Furthermore, the four-shot UDS acquisition achieved the best SNR performance in diffusion imaging with 12.11% and 40.85% improvements over the VDS and DDS acquisitions with the same readout duration, respectively. CONCLUSION: UDS sampling is an efficient spiral acquisition scheme for high-resolution diffusion imaging with reliable navigator information. It provides superior off-resonance performance and SNR efficiency over the VDS and DDS samplings for the tested scenarios.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética , Reprodutibilidade dos Testes , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Interpretação de Imagem Assistida por Computador/métodos , Artefatos , Processamento de Imagem Assistida por Computador/métodos , Imagem Ecoplanar
11.
Magn Reson Med ; 89(5): 1915-1930, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36594439

RESUMO

PURPOSE: To combine a new two-stage N/2 ghost correction and an adapted L1-SPIRiT method for reconstruction of 7T highly accelerated whole-brain diffusion MRI (dMRI) using only autocalibration scans (ACS) without the need of additional single-band reference (SBref) scans. METHODS: The proposed ghost correction consisted of a 3-line reference approach in stage 1 and the reference-free entropy method in stage 2. The adapted L1-SPIRiT method was formulated within the 3D k-space framework. Its efficacy was examined by acquiring two dMRI data sets at 1.05-mm isotropic resolutions with a total acceleration of 6 or 9 (i.e., 2-fold or 3-fold slice and 3-fold in-plane acceleration). Diffusion analysis was performed to derive DTI metrics and estimate fiber orientation distribution functions (fODFs). The results were compared with those of 3D k-space GRAPPA using only ACS, all in reference to 3D k-space GRAPPA using both ACS and SBref (serving as a reference). RESULTS: The proposed ghost correction eliminated artifacts more robustly than conventional approaches. Our adapted L1-SPIRiT method outperformed 3D k-space GRAPPA when using only ACS, improving image quality to what was achievable with 3D k-space GRAPPA using both ACS and SBref scans. The improvement in image quality further resulted in an improvement in estimation performances for DTI and fODFs. CONCLUSION: The combination of our new ghost correction and adapted L1-SPIRiT method can reliably reconstruct 7T highly accelerated whole-brain dMRI without the need of SBref scans, increasing acquisition efficiency and reducing motion sensitivity.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Imagem de Difusão por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Imagens de Fantasmas , Artefatos
12.
Wound Repair Regen ; 31(5): 688-699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37553788

RESUMO

Diabetes mellitus (DM) is a complex disease with alarming worldwide health implications and high mortality rates, largely due to its complications such as cardiovascular disease, nephropathy, neuropathy, and retinopathy. Recent research has shown that procyanidins (PC), a type of flavonoid, have strong antioxidant and free radical elimination effects, and may be useful in improving glucose metabolism, enhancing pancreatic islet cell activity, and decreasing the prevalence of DM complications. This review article presents a systematic search for peer-reviewed articles on the use of PC in the treatment of DM, without any language restrictions. The article also discusses the potential for PC to sensitise DM medications and improve their efficacy. Recent in vivo and in vitro studies have demonstrated promising results in improving the biological activity and bioavailability of PC for the treatment of DM. The article concludes by highlighting the potential for novel materials and targeted drug delivery methods to enhance the pharmacokinetics and bioactivity of PC, leading to the creation of safer and more effective anti-DM medications in the future.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Proantocianidinas , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Proantocianidinas/farmacologia , Proantocianidinas/uso terapêutico , Cicatrização , Complicações do Diabetes/complicações , Glucose
13.
Bioorg Med Chem Lett ; 80: 129101, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36481449

RESUMO

In this study, a series of structurally novel N-(benzene sulfonyl) acetamide derivatives were designed, synthesized, and biologically evaluated as COX-2/5-LOX/TRPV1 multitarget inhibitors for anti-inflammatory and analgesic therapy. Among them, 9a and 9b displayed favorable COX-2 (9a IC50 = 0.011 µM, 9b IC50 = 0.023 µM), 5-LOX (9a IC50 = 0.046 µM, 9b IC50 = 0.31 µM) and TRPV1 (9a IC50 = 0.008 µM, 9b IC50 = 0.14 µM) inhibitory activities. The pharmacokinetic (PK) study of 9a in SD rats at the dosage of 10 mg/kg demonstrated a high oral exposure, an acceptable clearance and a favorable bioavailability (Cmax = 5807.18 ± 2657.83 ng/mL, CL = 3.24 ± 1.47 mL/min/kg, F = 96.8 %). Further in vivo efficacy studies illustrated that 9a was capable of ameliorating formalin-induced pain and inhibiting capsaicin-induced ear edema.


Assuntos
Analgésicos , Benzeno , Ratos , Animais , Ciclo-Oxigenase 2/metabolismo , Ratos Sprague-Dawley , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Amidas/uso terapêutico , Acetamidas/farmacologia , Acetamidas/uso terapêutico , Relação Estrutura-Atividade , Edema/induzido quimicamente , Edema/tratamento farmacológico , Simulação de Acoplamento Molecular , Anti-Inflamatórios não Esteroides/farmacologia , Canais de Cátion TRPV
14.
Bioorg Med Chem ; 91: 117402, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37421709

RESUMO

Nitric oxide (NO) may be beneficial to overcoming drug resistance resulting from mutation of mTOR kinases and bypass mechanisms. In this study, a novel structural series of hybrids of mTOR inhibitor and NO donor were designed and synthesized via structure-based drug design (SBDD). Throughout the 20 target compounds, half of the compounds (13a, 13b, 19a-19d, 19f-19j) demonstrated attractive mTOR inhibitory activity with IC50 at single-digit nanomolar level. In particular, 19f exerted superior anti-proliferative activity against HepG2, MCF-7, HL-60 cells (HepG2, IC50 = 0.24 µM; MCF-7, IC50 = 0.88 µM; HL-60, IC50 = 0.02 µM) to that of the clinical investigated mTOR inhibitor MLN0128, and show mild cytotoxicity against normal cells with IC50 over 10 µM. 19a, with the most potent mTOR inhibitory activity in this series (IC50 = 3.31 nM), also displayed attractive cellular potency. In addition, 19f treatment in HL-60 reduces the levels of Phos-Akt and Phos-S6 in a dose-dependent manner, and releases NO in cells. In summary, 19f deserves further development as a novel mTOR-based multi-target anti-cancer agent.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Doadores de Óxido Nítrico/farmacologia , Serina-Treonina Quinases TOR , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Desenho de Fármacos , Relação Estrutura-Atividade , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Estrutura Molecular
15.
Ecotoxicol Environ Saf ; 249: 114461, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38321680

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are well known persistent organic pollutants that have carcinogenic, teratogenic, and mutagenic effects on humans and animals. Arbuscular mycorrhizal fungi (AMF) that can infest plant hosts and form symbioses may help plants to enhance potential rhizosphere effects, thus contributing to the rhizodegradation of PAH-contaminated soils. The present study aimed to assess the effectiveness of AMF on enhancing Salix viminalis-mediated phytoremediation of PAH-polluted soil and clarify the plant enzymatic and organic acid mechanisms induced by AMF. Natural attenuation (NA), phytoremediation (P, Salix viminalis), S. viminalis-AMF combined remediation using willow inoculated with Funneliformis mosseae (PM), Laroideoglomus etunicatum (PE), and Rhizophagus intraradices (PI) were used as strategies for the remediation of PAH-polluted soils. The results showed that AMF inoculation contributed to the dissipation of the high-molecular-weight PAH benzo (α) pyrene that had concentrations in PM, PE, and PI treatments of 40.1 %, 24.49 %, and 36.28 % of the level in the NA treatment, and 62.32 %, 38.05 %, and 56.38 % of the level in the P treatment after 90 days. The mycorrhizal treatment also improved the removal efficiency of phenanthrene and pyrene, as their concentrations were sharply decreased after 30 days compared to the NA and P treatments. The research further clarified the changes in rhizosphere substances induced by AMF. Organic acids including arachidonic acid, octadecanedioic acid, α-linolenic acid, 10,12,14-octadecarachidonic acid and 5-methoxysalicylic acid that can act as co-metabolic substrates for certain microbial species to metabolize PAHs were significantly increased in AMF-inoculated treatments. AMF inoculation also elevated the levels of polyphenol oxidase, laccase, and dehydrogenase, that played crucial roles in PAHs biodegradation. These findings provide an effective strategy for using AMF-assisted S. viminalis to remediate PAH-polluted soils, and the results have confirmed the key roles of organic acids and soil enzymes in plant-AMF combined remediation of PAHs.


Assuntos
Micorrizas , Hidrocarbonetos Policíclicos Aromáticos , Salix , Poluentes do Solo , Animais , Humanos , Micorrizas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Biodegradação Ambiental , Salix/metabolismo , Solo , Pirenos/metabolismo , Poluentes do Solo/análise , Raízes de Plantas/metabolismo
16.
J Integr Neurosci ; 22(5): 135, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37735118

RESUMO

BACKGROUND: Glioma is the most common intracranial malignancy. Immune-infiltration and tumour stemness are associated with the prognosis of glioma. Although pleckstrin homology containing family A, number 4 (PLEKHA4) is widely expressed in various human cancers, its role in glioma remains unclear. METHODS: We examined the features and clinical significance of PLEKHA4 in gliomas by analysing relevant data from the Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) databases. Gene set enrichment analysis (GSEA) was performed to determine the possible functions and pathways involving PLEKHA4 in glioma. The relationship between PLEKHA4 expression and the degree of oncogenic dedifferentiation was analysed using stemness scores (ss) calculated from epigenetic and transcriptomic features. We also explored the relationship between PLEKHA4 expression and immune cell infiltration in gliomas using the CIBERSORT databases. Furthermore, drug sensitivity analysis was performed using datasets from the GDSC and GTRP databases. In addition, we performed relevant in vitro experimental studies. RESULTS: PLEKHA4 DNA hypomethylation status was associated with its high expression in glioma tissues as well as poor prognoses. Univariate and multivariate Cox analyses indicated that PLEKHA4 expression may be considered as an independent prognostic factor in patients with glioma. GSEA indicated that high PLEKHA4 expression was associated with Janus kinase (JAK)/signal transducer and activator of transcription (STAT), Wingless-Type MMTV Integration Site Family (Wnt), JUN N-terminal kinase (JNK) signalling pathways and involved in apoptotic, cytoskeletal, and cell adhesion biological processes (BPs). In addition, increased PLEKHA4 expression was associated with higher glioma stemness scores than lower PLEKHA4 expression levels. Furthermore, the expression of PLEKHA4 was shown to be associated with glioma infiltration by CD4+ T cells, B cells, neutrophils, macrophages, and dendritic cells. Drug sensitivity analysis also showed that PLEKHA4 expression was negatively correlated with the sensitivity of several small molecule kinase inhibitors. Furthermore, in vitro experiments confirmed that PLEKHA4 knockdown inhibited the proliferation of glioma cells. CONCLUSIONS: PLEKHA4 is highly expressed in glioma tissues and correlated with tumour stemness, immune cell infiltration and proliferation, suggesting its potential as a novel prognostic biomarker and therapeutic target in glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Povo Asiático , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Proliferação de Células/genética , Glioma/genética , Glioma/imunologia , Células-Tronco Neoplásicas/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
17.
Entropy (Basel) ; 25(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37628205

RESUMO

Entropy quantification approaches have gained considerable attention in engineering applications. However, certain limitations persist, including the strong dependence on parameter selection, limited discriminating power, and low robustness to noise. To alleviate these issues, this paper introduces two novel algorithms for time series analysis: the ensemble improved permutation entropy (EIPE) and multiscale EIPE (MEIPE). Our approaches employ a new symbolization process that considers both permutation relations and amplitude information. Additionally, the ensemble technique is utilized to reduce the dependence on parameter selection. We performed a comprehensive evaluation of the proposed methods using various synthetic and experimental signals. The results illustrate that EIPE is capable of distinguishing white, pink, and brown noise with a smaller number of samples compared to traditional entropy algorithms. Furthermore, EIPE displays the potential to discriminate between regular and non-regular dynamics. Notably, when compared to permutation entropy, weighted permutation entropy, and dispersion entropy, EIPE exhibits superior robustness against noise. In practical applications, such as RR interval data classification, bearing fault diagnosis, marine vessel identification, and electroencephalographic (EEG) signal classification, the proposed methods demonstrate better discriminating power compared to conventional entropy measures. These promising findings validate the effectiveness and potential of the algorithms proposed in this paper.

18.
Magn Reson Med ; 88(2): 727-741, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35403237

RESUMO

PURPOSE: To propose a novel deep learning (DL) approach to transmit-B1 (B1+ )-artifact mitigation without direct use of parallel transmission (pTx), by predicting pTx images from single-channel transmission (sTx) images. METHODS: A deep encoder-decoder convolutional neural network was constructed and trained to learn the mapping from sTx to pTx images. The feasibility was demonstrated using 7 T Human-Connectome Project (HCP)-style diffusion MRI. The training dataset comprised images acquired on 5 healthy subjects using commercial Nova RF coils. Relevant hyperparameters were tuned with a nested cross-validation, and the generalization performance evaluated using a regular cross-validation. RESULTS: Our DL method effectively improved the image quality for sTx images by restoring the signal dropout, with quality measures (including normalized root-mean-square error, peak SNR, and structural similarity index measure) improved in most brain regions. The improved image quality was translated into improved performances for diffusion tensor imaging analysis; our method improved accuracy for fractional anisotropy and mean diffusivity estimations, reduced the angular errors of principal eigenvectors, and improved the fiber orientation delineation relative to sTx images. Moreover, the final DL model trained on data of all 5 subjects was successfully used to predict pTx images for unseen new subjects (randomly selected from the 7 T HCP database), effectively recovering the signal dropout and improving color-coded fractional anisotropy maps with largely reduced noise levels. CONCLUSION: The proposed DL method has potential to provide images with reduced B1+ artifacts in healthy subjects even when pTx resources are inaccessible on the user side.


Assuntos
Artefatos , Aprendizado Profundo , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador/métodos
19.
Bioorg Med Chem Lett ; 56: 128464, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34808388

RESUMO

Non-alcoholic steatohepatitis (NASH) is a serious form of non-alcoholic fatty liver disease (NAFLD) characterized by liver steatosis with lobular inflammation, hepatocyte injury and pericellular fibrosis. JBP485 is a hydrophilic dipeptide with protective effects on liver through alleviation of oxidative stress and inhibition of hepatocyte apoptosis and ICAM-1 expression. Vitamin E (VE), as a powerful biological antioxidant, exerts a certain protective effect on cell membranes and lipoproteins from lipid peroxidation. In this study, on the basis of the structural characteristics of two agents, the prodrug form target of JBP485 and VE (JBP485-VE) was designed and synthesized via succinic acid linker. The synthesized compound significantly reduced the degree of inflammation and fibrosis according to hematoxylin-eosin (H&E) and sirius red staining assay for the liver tissue in CCl4-induced NASH mouse model. The clear reduction of TG, T-CHO and ALT, AST content also demonstrated its efficacy in the treatment of NASH. In addition, JBP485-VE also reduced the expression of the inflammatory markers IL-2, IL-17A and malondialdehyde (MDA) in liver tissue, which indicated its higher anti-inflammatory and anti-oxidative stress activity. All these evaluated biological properties suggest that the strategy of prodrug design provided an effective method for the treatment of NASH.


Assuntos
Desenho de Fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Peptídeos Cíclicos/farmacologia , Pró-Fármacos/farmacologia , Vitamina E/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Tetracloreto de Carbono , Relação Dose-Resposta a Droga , Fibrose/induzido quimicamente , Fibrose/tratamento farmacológico , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Camundongos , Estrutura Molecular , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Tamanho do Órgão/efeitos dos fármacos , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Relação Estrutura-Atividade , Vitamina E/síntese química , Vitamina E/química
20.
Cell Biol Toxicol ; 38(3): 531-551, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34455488

RESUMO

Diabetes mellitus (DM) is a metabolic syndrome, caused by insufficient insulin secretion or insulin resistance (IR). DM enhances oxidative stress and induces mitochondrial function in different kinds of cell types, including pancreatic ß-cells. Our previous study has showed phosphocreatine (PCr) can advance the mitochondrial function through enhancing the oxidative phosphorylation and electron transport ability in mitochondria damaged by methylglyoxal (MG). Our aim was to explore the potential role of PCr as a molecule to protect mitochondria from diabetes-induced pancreatic ß-cell injury with insulin secretion deficiency or IR through dual AKT/IRS-1/GSK-3ß and STAT3/Cyclophilin D (Cyp-D) signaling pathways. MG-induced INS-1 cell viability, apoptosis, mitochondrial division and fusion, the morphology, and function of mitochondria were suppressed. Flow cytometry was used to detect the production of intracellular reactive oxygen species (ROS) and the changes of intracellular calcium, and the respiratory function was measured by oxygraph-2k. The expressions of AKT, IRS-1, GSK-3ß, STAT3, and Cyp-D were detected using Western blot. The result showed that the oxidative stress-related kinases were significantly restored to the normal level after the pretreatment with PCr. Moreover, PCr pretreatment significantly inhibited cell apoptosis, decreased intracellular calcium, and ROS production, and inhibited mitochondrial division and fusion, and increased ATP synthesis damaged by MG in INS-1 cells. In addition, pretreatment with PCr suppressed Cytochrome C, p-STAT3, and Cyp-D expressions, while increased p-AKT, p-IRS-1, p-GSK-3ß, caspase-3, and caspase-9 expressions. In conclusion, PCr has protective effect on INS-1 cells in vitro and in vivo, relying on AKT mediated STAT3/ Cyp-D pathway to inhibit oxidative stress and restore mitochondrial function, signifying that PCr might become an emerging candidate for the cure of diabetic pancreatic cancer ß-cell damage.


Assuntos
Cálcio , Proteínas Proto-Oncogênicas c-akt , Apoptose , Cálcio/metabolismo , Peptidil-Prolil Isomerase F , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Proteínas Substratos do Receptor de Insulina/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Fosfocreatina/metabolismo , Fosfocreatina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
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