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

ABSTRACT

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.
J Am Chem Soc ; 146(37): 25813-25823, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39236157

ABSTRACT

Electrocatalytic coupling of CO2 and NO3- to urea is a promising way to mitigate greenhouse gas emissions, reduce waste from industrial processes, and store renewable energy. However, the poor selectivity and activity limit its application due to the multistep process involving diverse reactants and reactions. Herein, we report the first work to design heterostructured Cu-Bi bimetallic catalysts for urea electrosynthesis. A high urea Faradaic efficiency (FE) of 23.5% with a production rate of 2180.3 µg h-1 mgcat-1 was achieved in H-cells, which surpassed most reported electrocatalysts in the literature. Moreover, the catalyst had a remarkable recycling stability. Experiments and density functional theory calculations demonstrated that introduction of moderate Bi induced the formation of the Bi-Cu/O-Bi/Cu2O heterostructure with abundant phase boundaries, which are beneficial for NO3-, CO2, and H2O activation and enhance C-N coupling and promote *HONCON intermediate formation. Moreover, favorable *HNCONH2 protonation and urea desorption processes were also validated, further explaining the reason for high activity and selectivity toward urea.

3.
Small ; : e2403099, 2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38973084

ABSTRACT

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.

4.
Langmuir ; 40(37): 19575-19588, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39230955

ABSTRACT

Shotcrete is a crucial component of tunnel engineering. To investigate the impact of fluoride-containing alkali-free liquid accelerators on the structural safety of shotcrete, this study prepared shotcrete using three different fluoride-based alkali-free liquid accelerators: magnesium fluosilicate, fluosilicic acid, and hydrofluoric acid. The corrosion of steel rebar within the shotcrete was examined and compared with that of shotcrete prepared using a fluoride-free alkali-free liquid accelerator. Analysis of the hydration products and pore structure of the shotcrete revealed that fluoride-containing accelerators inhibited the hydration of C3S, increased the content of harmful pores, reduced the pH value, and decreased the chloride ion binding capacity of the shotcrete. As a result, steel reinforcement within the fluoride-containing shotcrete was not effectively protected during the early stages. Detection of corrosion products indicated that shotcrete containing fluosilicic acid and hydrofluoric acid accelerators led to the rapid formation of loose corrosion products, primarily Fe2O3, thereby accelerating the corrosion rate of the steel reinforcement. Among the accelerators studied, hydrofluoric acid posed the most severe threat to the reinforcement, with the open circuit potential reaching -520.2 mV after 24 days of accelerated corrosion testing. Additionally, the mechanisms by which fluorides influence the corrosion of steel reinforcement in shotcrete were explored through the analysis of concrete hydration products and corrosion products on the steel rebar.

5.
Eur Radiol ; 34(4): 2759-2771, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37736802

ABSTRACT

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.


Subject(s)
Brain Neoplasms , Connectome , Glioma , Humans , Diffusion Tensor Imaging/methods , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Retrospective Studies , Quality of Life , Glioma/diagnostic imaging , Glioma/surgery
6.
Eur Radiol ; 34(2): 1349-1357, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37581664

ABSTRACT

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.


Subject(s)
Laminoplasty , Spinal Cord Diseases , Spondylosis , Humans , Aged , Diffusion Tensor Imaging/methods , Follow-Up Studies , Laminoplasty/adverse effects , Spondylosis/complications , Spondylosis/diagnostic imaging , Spondylosis/surgery , Spinal Cord Diseases/diagnostic imaging , Spinal Cord Diseases/surgery , Spinal Cord Diseases/complications , Spinal Cord , Cervical Vertebrae/surgery , Perfusion
7.
Inorg Chem ; 63(36): 16842-16854, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39178218

ABSTRACT

Transition metal-based oxides with similar oxidation activities for catalytic hydrocarbon combustion have attracted much attention. In this study, a new class of metal high-entropy oxides (CoxMnNiFeAl)3O4 (x = 1, 2, 3, 4, 5) with a porous structure was fabricated through a simple and inexpensive NaCl template-assisted sol-gel approach, which was employed for the catalytic oxidation of propane. The results indicated that the content of cobalt has a great impact on its activity, and the (Co4MnNiFeAl)3O4 catalyst exhibited the best catalytic activity. At the high space velocity of 60 000 mL·g-1·h-1, the optimized one with high-temperature treatment can still achieve 90% propane conversion at 309 °C, which is 68 and 178 °C lower than those of the (CoMnNiFeAl)3O4 catalyst and pure cobalt oxide, respectively. Meanwhile, it has the lowest apparent activation energy (46.6 KJ·mol-1) and the fastest reaction rate (26.976 × 10-6 mol·gcat-1·s-1 at 290 °C). The improved performance of the (Co4MnNiFeAl)3O4 catalyst could be attributed to the enhancement of low-temperature reducibility, the increased number of reactive surface oxygen species, and the cocktail effect of the high-entropy oxides. This work provides new insights into the preparation of efficient light alkane degradation catalysts and a realistic approach for the large-scale application of high-entropy oxides in the field of oxidation catalysts.

8.
J Nat Prod ; 87(6): 1643-1651, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38848113

ABSTRACT

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.


Subject(s)
Penicillium , Pyrones , Pyrones/chemistry , Pyrones/pharmacology , Pyrones/isolation & purification , Penicillium/chemistry , Humans , Molecular Structure , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Drug Screening Assays, Antitumor , Cell Line, Tumor
9.
J Nanobiotechnology ; 22(1): 34, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38238748

ABSTRACT

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.


Subject(s)
Adhesives , Wound Healing , Humans , Rats , Animals , Swine , Adhesives/pharmacology , Skin , Bandages
10.
Clin Exp Pharmacol Physiol ; 51(8): e13904, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38923060

ABSTRACT

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.


Subject(s)
Apoptosis , Autophagy , Myocardial Reperfusion Injury , Nerve Tissue Proteins , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Animals , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Apoptosis/drug effects , Nerve Tissue Proteins/metabolism , Male , Autophagy/drug effects , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Rats , Oxidative Stress/drug effects , Rats, Sprague-Dawley
11.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Article in English | MEDLINE | ID: mdl-34810249

ABSTRACT

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.

12.
J Med Internet Res ; 26: e49688, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39250790

ABSTRACT

BACKGROUND: With the exacerbation of population aging, the health issues of middle-aged and older adults have increasingly become a focus of attention. The widespread use of the internet has created conditions for promoting the health of this demographic. However, little is known about the effects of information access in promoting the relationship between internet use and the health of middle-aged and older adults. OBJECTIVE: This study aims to examine the relationship between internet use and multidimensional health in middle-aged and older adults, as well as the mediating effect of information access. Moreover, this study will explore the relationship between other dimensions of internet use (purposes and frequency) and health. METHODS: Data were sourced from the China General Social Survey conducted in 2018. Health outcomes, including self-rated, physical, and mental health, were assessed using the 5-level self-rated health scale, the 5-level basic activities of daily living scale, and the 5-level depression scale, respectively. The ordinal logistic regression model was used to examine the relationship between internet use and health among middle-aged and older adults. Additionally, the Karlson-Holm-Breen decomposition method was used to examine the mediation effect of information access. To address endogeneity issues, the two-stage least squares approach was applied. RESULTS: In our sample, nearly half (n=3036, 46.3%) of the respondents use the internet. Regression analyses revealed that internet use was positively associated with self-rated health (odds ratio [OR] 1.55, 95% CI 1.39-1.74; P<.001), physical health (OR 1.39, 95% CI 1.25-1.56; P<.001), and mental health (OR 1.33, 95% CI 1.19-1.49; P<.001) of middle-aged and older adults. Various dimensions of internet use positively contribute to health. In addition, information access significantly mediated the relationship between internet use and self-rated health (ß=.28, 95% CI 0.23-0.32), physical health (ß=.40, 95% CI 0.35-0.45), and mental health (ß=.16, 95% CI 0.11-0.20). Furthermore, there were significant differences in the relationship between internet use and health among advantaged and disadvantaged groups. CONCLUSIONS: The study showed that different dimensions of internet use are associated with better self-rated health, better physical health, and better mental health in middle-aged and older adults. Information access mediates the relationship between internet use and health. This result emphasizes the significance of promoting internet access as a means to enhance the health of middle-aged and older adults in China.


Subject(s)
Health Status , Internet Use , Humans , Cross-Sectional Studies , Middle Aged , Aged , Male , Female , China , Internet Use/statistics & numerical data , Access to Information , Internet/statistics & numerical data , Mental Health/statistics & numerical data , Activities of Daily Living
13.
J Stroke Cerebrovasc Dis ; 33(11): 107882, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39038628

ABSTRACT

BACKGROUND AND AIM: The association of Lipoprotein(a) (Lp[a]) with recurrent ischemic events in stented patients remains uncertain. So, this research aimed to investigate the impact of elevated Lp(a) levels on the occurrence of ischemic events in this specific patient population. METHODS: Totally 553 patients who underwent intracranial or extracranial artery stent implantation were included. Baseline data were collected and postoperative ischemic outcomes were followed up. Cox regression analysis was used to investigate the association between Lp(a) and outcomes, while accounting for confounding factors. Finally, we established prediction models based on nomogram. RESULTS: Of total 553 patients, a number of 107 (19.3%) experienced outcomes. These included 46 cases (25.4%) in group with elevated Lp(a) levels (>30 mg/dL) and 61 cases (16.4%) in non-elevated group (χ2=6.343, p=0.012). The group with elevated Lp(a) was 1.811 times more likely to experience ischemic events than the non-elevated group, each 1 mg/dL increase in Lp(a) resulted in a 1.008-fold increase in the recurrence rate of ischemic events. In addition, sex (male), previous history of coronary heart disease, decreased albumin, elevated very low density lipoprotein cholesterol and poorly controlled risk factors (including blood pressure and blood sugar) were also associated with a high risk of recurrent ischemic events after stent implantation. CONCLUSION: Lp(a) elevation was a significant risk factor for ischemic events in symptomatic patients who underwent intracranial or extracranial artery stenting.

14.
J Environ Manage ; 370: 122503, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39299104

ABSTRACT

Arbuscular mycorrhizal fungi (AMF) are positive to the phytoremediation by improving plant biomass and soil properties. However, the role of AM plants to the remediation of polycyclic aromatic hydrocarbons (PAHs) is yet to be widely recognized, and the impact of AM plants to indigenous microbial communities during remediation remains unclear. In this work, a 90-day study was conducted to assess the effect of AMF-Salix viminalis on the removal of PAHs, and explore the impact to the microbial community composition, abundance, and function. Results showed that AMF-Salix viminalis effectively enhanced the removal of benzo[a]pyrene, and enriched more PAH-degrading bacteria, consisting of Actinobacteria, Chloroflexi, Sphingomonas, and Stenotrophobacter, as well as fungi including Basidiomycota, Pseudogymnoascus, and Tomentella. For gene function, AM willow enhanced the enrichment of genes involved in amino acid synthesis, aminoacyl-tRNA biosynthesis, and cysteine and methionine metabolism pathways. F. mosseae inoculation had a greater effect on alpha- and beta-diversity of microbial genes at 90 d. Additionally, AMF inoculation significantly increased the soil microbial biomass carbon and organic matter concentration. All together, the microbial community assembly and function shaped by AM willow promoted the dissipation of PAHs. Our results support the effectiveness of AM remediation and contribute to reveal the enhancing-remediation mechanism to PAHs using multi-omics data.

15.
Angew Chem Int Ed Engl ; : e202410972, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39115031

ABSTRACT

Coupling in situ generated intermediates with other substrates/intermediates is a viable approach for diversifying product outcomes of catalytic reactions involving two or multiple reactants. Cyclohexanone oxime is a key precursor for caprolactam synthesis (the monomer of Nylon-6), yet its current production uses unsustainable carbon sources, noble metal catalysts, and harsh conditions. Herein, we report the first work to synthesize cyclohexanone oxime through electroreduction of phenol and hydroxylamine. The Faradaic efficiency reached 69.1% over Cu catalyst, accompanied by a corresponding cyclohexanone oxime formation rate of 82.0 g h-1 gcat-1. In addition, the conversion of phenol was up to 97.5%. In situ characterizations, control experiments, and theoretical calculations suggested the importance of balanced activation of water, phenol, and hydroxylamine substrates on the optimal metallic Cu catalyst for achieving high-performance cyclohexanone oxime synthesis. Besides, a tandem catalytic route for the upgrading of lignin to caprolactam has been successfully developed through the integration of thermal catalysis, electrocatalysis, and Beckmann rearrangement, which achieved the synthesis of 0.40 g of caprolactam from 4.0 g of lignin raw material.

16.
J Am Chem Soc ; 145(40): 21945-21954, 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37751566

ABSTRACT

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.

17.
Magn Reson Med ; 90(1): 133-149, 2023 07.
Article in English | MEDLINE | ID: mdl-36883748

ABSTRACT

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.


Subject(s)
Algorithms , Diffusion Magnetic Resonance Imaging , Reproducibility of Results , Diffusion Magnetic Resonance Imaging/methods , Diffusion Tensor Imaging/methods , Image Interpretation, Computer-Assisted/methods , Artifacts , Image Processing, Computer-Assisted/methods , Echo-Planar Imaging
18.
Magn Reson Med ; 89(5): 1915-1930, 2023 05.
Article in English | MEDLINE | ID: mdl-36594439

ABSTRACT

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.


Subject(s)
Algorithms , Image Processing, Computer-Assisted , Image Processing, Computer-Assisted/methods , Diffusion Magnetic Resonance Imaging , Brain/diagnostic imaging , Phantoms, Imaging , Artifacts
19.
Wound Repair Regen ; 31(5): 688-699, 2023.
Article in English | MEDLINE | ID: mdl-37553788

ABSTRACT

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.


Subject(s)
Diabetes Complications , Diabetes Mellitus, Type 2 , Proanthocyanidins , Humans , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Proanthocyanidins/pharmacology , Proanthocyanidins/therapeutic use , Wound Healing , Diabetes Complications/complications , Glucose
20.
Bioorg Med Chem Lett ; 80: 129101, 2023 01 15.
Article in English | MEDLINE | ID: mdl-36481449

ABSTRACT

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.


Subject(s)
Analgesics , Benzene , Rats , Animals , Cyclooxygenase 2/metabolism , Rats, Sprague-Dawley , Analgesics/pharmacology , Analgesics/therapeutic use , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2 Inhibitors/therapeutic use , Amides/therapeutic use , Acetamides/pharmacology , Acetamides/therapeutic use , Structure-Activity Relationship , Edema/chemically induced , Edema/drug therapy , Molecular Docking Simulation , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , TRPV Cation Channels
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