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1.
J Formos Med Assoc ; 2024 May 09.
Article En | MEDLINE | ID: mdl-38729819

BACKGROUND AND PURPOSE: Patients with hypervascular spinal tumors may have severe blood loss during tumor resection, which increases the risks of perioperative morbidity and mortality. However, the preoperative evaluation of tumor vascularity may be challenging; moreover, the reliability of the data obtained in conventional preoperative noninvasive imaging is debatable. In this study, we compared conventional magnetic resonance imaging (MRI) and subtraction computed tomography angiography (CTA) in terms of their performance in vascularity evaluation. The catheter digital subtraction angiography (DSA) technique was used as a reference standard. METHODS: This study included 123 consecutive patients with spinal tumor who underwent subtraction CTA, catheter DSA, and subsequent surgery between October 2015 and October 2021. Data regarding qualitative and semiquantitative subtraction CTA parameters and conventional MRI signs were collected for comparison with tumor vascularity graded through catheter DSA. The diagnostic performance of qualitative CTA, quantitative CTA, and conventional MRI in assessing spinal tumor vascularity was analyzed. RESULTS: Qualitative subtraction CTA was the best noninvasive imaging modality in terms of diagnostic performance (area under the receiver operating characteristic curve [AUROC], 0.95). Quantitative CTA was relatively inferior (AUROC, 0.87). MRI results had low reliability (AUROC, 0.51 to 0.59). Intratumoral hemorrhage and prominent foraminal venous plexus were found to be the specific signs for hypervascularity (specificity 93.2%). CONCLUSIONS: Qualitative subtraction CTA offers the highest diagnostic value in evaluating spinal tumor vascularity, compared to quantitative CTA and MRI. Although conventional MRI may not be a reliable approach, certain MRI signs may have high specificity, which may be crucial for assessing spinal tumor vascularity.

2.
Jpn J Radiol ; 2024 May 06.
Article En | MEDLINE | ID: mdl-38705936

PURPOSE: Mycobacterium abscessus complex (MABC) commonly causes lung disease (LD) and has a high treatment failure rate of around 50%. In this study, our objective is to investigate specific CT patterns for predicting treatment prognosis and monitoring treatment response, thus providing valuable insights for clinical physicians in the management of MABC-LD treatment. METHODS: We retrospectively assessed 34 patients with MABC-LD treated between January 2015 and December 2020. CT scores for bronchiectasis, cellular bronchiolitis, consolidation, cavities, and nodules were measured at initiation and after treatment. The ability of the CT scores to predict treatment outcomes was analyzed in logistic regression analyses. RESULTS: The CT scoring system had excellent inter-reader agreement (all intraclass correlation coefficients, > 0.82). The treatment failure (TF) group (17/34; 50%) had higher cavitation diameter (p = 0.049) and extension (p = 0.041) at initial CT and higher cavitation diameter (p = 0.049) and extension (p =0 .045), consolidation (p = 0.022), and total (p = 0.013) scores at follow-up CT than the treatment success (TS) group. The changes of total score and consolidation score (p = 0.049 and 0.024, respectively) increased in the TF group more than the TS group between the initial and follow-up CT. Multivariable logistic regression analysis showed initial cavitation extension, follow-up consolidation extension, and change in consolidation extension (adjusted odds ratio: 2.512, 2.495, and 9.094, respectively, per 1-point increase; all p < 0.05) were significant predictors of treatment failure. CONCLUSIONS: A high pre-treatment cavitation extension score and an increase in the consolidation extension score during treatment on CT could be alarm signs of treatment failure requiring tailor the treatment of MABC-LD carefully.

3.
J Pain Res ; 17: 1381-1391, 2024.
Article En | MEDLINE | ID: mdl-38618296

Purpose: Chinese herbal medicine and electroacupuncture (EA) have been used to control pain for many decades in China. We aim to explore the efficacy of intervening patients whose discogenic sciatica symptoms lasting longer than 3 months with these conservative treatments. Patients and Methods: This is a single-center, parallel-group, patient-unblinded Randomized Controlled Trial (RCT) with blinded outcome assessment and statistician. One hundred and twenty-four patients will be assigned randomly into 2 groups including conservative treatment group (Shenxie Zhitong capsule combined with EA treatment) and Nonsteroidal Anti-inflammatory Drugs (Nonsteroidal Anti-inflammatory Drugs, NSAIDs) control group (Celecoxib) in a 1:1 ratio. The trial involves a 4-week treatment along with follow-up for 6 months. The primary outcome is the leg pain intensity measured by the visual analogue scale (VAS) at 6 months after randomization. Secondary outcomes include leg pain intensity at other time points, back pain intensity, leg pain and back pain frequency, functional status, quality of life, return to work status and satisfaction of patients. Adverse events will also be recorded. Strengths and Limitations of This Study: Through this study, we want to observe the efficacy of electroacupuncture combined with Chinese herbal medicine on pain intensity for chronic sciatica secondary to Lumbar Disc Herniation. If the final results are favorable, it is expected to be a safe, economical, and effective treatment for patients. The study design has the following limitations: the setup of control group was less than perfect; patients and doctors could not be blinded in this trial; we skipped the feasibility study. We have tried our best to minimize adverse impacts. Trial Registration: ChiCTR2300070884 (Chinese Clinical Trial Registry, http://www.chictr.org.cn, registered on 25th April 2023).

4.
Microb Pathog ; 190: 106628, 2024 May.
Article En | MEDLINE | ID: mdl-38508422

Rotavirus infections in suckling and weaning piglets cause severe dehydration and death, resulting in significant economic losses in the pig breeding industry. With the continuous emergence of porcine rotavirus (PoRV) variants and poor vaccine cross-protection among various genotypes, there is an urgent need to develop alternative strategies such as seeking effective antiviral products from nature, microbial metabolites and virus-host protein interaction. Sialidases play a crucial role in various physiopathological processes and offer a promising target for developing antivirus drugs. However, the effect of bacterial-derived sialidases on the infection of PoRVs remains largely unknown. Herein, we investigated the impact of bacterial-derived sialidases (sialidase Cp and Vc) on PoRV strain OSU(Group A) infection, using differentiated epithelial monkey kidney cells (MA104) as a model. Our results indicated that the pretreatment of MA104 with exogenous sialidases effectively suppressed PoRV OSU in a concentration-dependent manner. Notably, even at a concentration of 0.01 µU/mL, sialidases significantly inhibited the virus (MOI = 0.01). Meanwhile, we found that sialidase Vc pretreatment sharply reduced the binding rate of PoRV OSU. Last, we demonstrated that PoRV OSU might recognize α-2,3-linked sialic acid as the primary attachment factor in MA104. Our findings provide new insights into the underlying mechanism of PoRV OSU infections, shedding lights on the development of alternative antivirus approaches based on bacteria-virus interaction.


Neuraminidase , Rotavirus Infections , Rotavirus , Virus Replication , Animals , Neuraminidase/metabolism , Neuraminidase/genetics , Rotavirus/drug effects , Rotavirus/physiology , Swine , Virus Replication/drug effects , Cell Line , Epithelial Cells/virology , Epithelial Cells/microbiology , Virus Attachment/drug effects , N-Acetylneuraminic Acid/metabolism , N-Acetylneuraminic Acid/pharmacology , Antiviral Agents/pharmacology , Haplorhini , Swine Diseases/virology , Swine Diseases/microbiology
5.
Adv Sci (Weinh) ; : e2309869, 2024 Mar 28.
Article En | MEDLINE | ID: mdl-38544479

Ruthenium (Ru) is a promising electrocatalyst for the hydrogen evolution reaction (HER), despite suffering from low activity in non-acidic conditions due to the high kinetic energy barrier of H2O dissociation. Herein, the synthesis of carbon nanosheet-supported RuP/Ru heterostructures (RuP/Ru@CNS) from a natural polysaccharide is reported and demonstrates its behavior as an effective HER electrocatalyst in non-acidic conditions. The RuP/Ru@CNS exhibits low overpotential (106 mV at 200 mA·cm-2) in alkaline electrolyte, exceeding most reported Ru-based electrocatalysts. The electron shuttling between Ru atoms at the RuP/Ru interface results in a lowered energy barrier for H2O dissociation by electron-deficient Ru atoms in the pure Ru phase, as well as optimized H* adsorption of electron-gaining Ru atoms in the neighboring RuP. A low H* spillover energy barrier between Ru atoms at the RuP/Ru interface further boosts HER kinetics. This study demonstrates a sustainable method for the fabrication of efficient Ru-based electrocatalysts and provides a more detailed understanding of interface effects in HER catalysis.

6.
Nanoscale ; 16(8): 4205-4211, 2024 Feb 22.
Article En | MEDLINE | ID: mdl-38324361

Using first-principles calculations, we report the realization of multiferroics in an intrinsic ferroelectric α-Ga2S3 monolayer. Our results show that the presence of intrinsic gallium vacancies, which is the origin of native p-type conductivity, can simultaneously introduce a ferromagnetic ground state and a spontaneous out-of-plane polarization. However, the high switching barrier and thermodynamic irreversibility of the ferroelectric reversal path disable the maintenance of ferroelectricity, suggesting that the defect-free form should be a prerequisite for Ga2S3 to be multiferroic. Through applying strain, the behavior of spontaneous polarization of the pristine α-Ga2S3 monolayer can be effectively regulated, but the non-magnetic ground state does not change. Strikingly, via an appropriate concentration of hole doping, stable ferromagnetism with a high Curie temperature and robust ferroelectricity can be concurrently introduced in the α-Ga2S3 monolayer. Our work provides a feasible method for designing 2D multiferroics with great potential in future device applications.

7.
Nat Commun ; 15(1): 1097, 2024 Feb 06.
Article En | MEDLINE | ID: mdl-38321034

Bimetallic PtRu are promising electrocatalysts for hydrogen oxidation reaction in anion exchange membrane fuel cell, where the activity and stability are still unsatisfying. Here, PtRu nanowires were implanted with a series of oxophilic metal atoms (named as i-M-PR), significantly enhancing alkaline hydrogen oxidation reaction (HOR) activity and stability. With the dual doping of In and Zn atoms, the i-ZnIn-PR/C shows mass activity of 10.2 A mgPt+Ru-1 at 50 mV, largely surpassing that of commercial Pt/C (0.27 A mgPt-1) and PtRu/C (1.24 A mgPt+Ru-1). More importantly, the peak power density and specific power density are as high as 1.84 W cm-2 and 18.4 W mgPt+Ru-1 with a low loading (0.1 mg cm-2) anion exchange membrane fuel cell. Advanced experimental characterizations and theoretical calculations collectively suggest that dual doping with In and Zn atoms optimizes the binding strengths of intermediates and promotes CO oxidation, enhancing the HOR performances. This work deepens the understanding of developing novel alloy catalysts, which will attract immediate interest in materials, chemistry, energy and beyond.

8.
J Phys Chem Lett ; 15(4): 1121-1129, 2024 Feb 01.
Article En | MEDLINE | ID: mdl-38263631

Using first-principles calculations combined with a constant-potential implicit solvent model, we comprehensively studied the activity of oxygen electrode reactions catalyzed by electride-supported FeN4-embedded graphene (FeN4Cx). The physical quantities in FeN4Cx/electrides, i.e., work function of electrides, interlayer spacing, stability of heterostructures, charge transferred to Fe, d-band center of Fe, and adsorption free energy of O, are highly intercorrelated, resulting in activity being fully expressed by the nature of the electrides themselves, thereby achieving a precise modulation in activity by selecting different electrides. Strikingly, the FeN4PDCx/Ca2N and FeN4PDCx/Y2C systems maintain a high oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) activity with the overpotential less than 0.46 and 0.62 V in a wide pH range. This work provides an effective strategy for the rational design of efficient bifunctional catalysts as well as a model system with a simple activity-descriptor, helping to realize significant advances in energy devices.

9.
BMC Public Health ; 24(1): 117, 2024 01 08.
Article En | MEDLINE | ID: mdl-38191440

BACKGROUND: As global aging intensifies, older adults with chronic diseases are of increasing concern. Home and community-based services (HCBSs) have been proven to promote self-rated health (SRH) in older adults, but no research explored the associations between the use of overall HCBSs, three different types of HCBSs (health care, daily care, and social support services) and SRH among older adults with chronic diseases. Consequently, this study applies a national publicly available database to examine these associations among older adults with chronic diseases. METHODS: 8,623 older adults with chronic diseases (≥ 60 years old) were included in this study. SRH was evaluated applying a concise question with a 1 - 5 scale. HCBSs utilization was assessed through the question, "What kind of HCBSs were used in the community?". Univariate general linear regression models aimed to compare the mean values of SRH in terms of HCBSs utilization in each group. This study is a cross-sectional study design and the relationship between HCBSs utilization and SRH was assessed by multilevel linear regression. RESULTS: The mean score for SRH among the respondents was 3.19, of whom 20.55% used one or more HCBSs, 19.47% utilized health care services, 2.44% utilized social support services, and only 0.55% utilized daily care services. The use of HCBSs was found to be linked to SRH among older adults with chronic diseases (ß = 0.085, SE = 0.025, p < 0.001). SRH among older adults with chronic diseases was strongly linked to the use of health care and social support services (ß = 0.068, SE = 0.025, p < 0.001; ß = 0.239, SE = 0.063, p < 0.001, respectively). However, there was no significant association between the use of daily care services and SRH among older adults with chronic diseases. CONCLUSION: This study revealed that HCBSs utilization was positively and significantly linked to SRH in Chinese older adults with chronic diseases. Furthermore, this study supposes the low utilization of social support and daily care services may be due to a mismatch between supply and demand. The government should offer the targeted HCBSs for older adults with chronic diseases according to their unique features to enhance their health status.


Facilities and Services Utilization , Retirement , Humans , Aged , Middle Aged , Cross-Sectional Studies , Longitudinal Studies , Community Health Services , China , Chronic Disease
10.
J Pharm Pharmacol ; 76(3): 236-244, 2024 Mar 04.
Article En | MEDLINE | ID: mdl-38183672

OBJECTIVES: The mechanisms underlying the therapeutic effects of Si-Zhi Wan (SZW), a traditional Chinese medicine used to treat osteoporosis (OP), remain unknown. This study investigated the therapeutic effects of SZW on mice that underwent ovariectomy (OVX) and underlying mechanisms thereof. METHODS: We established an in vivo model of OP by performing OVX in mice. Microcomputed tomography (Micro-CT) was used to assess changes in bone characteristics of mice following SZW administration for 4 weeks. H&E staining revealed alterations in bone tissues of mice. Osteoclastogenesis in mouse bone tissue was observed using tartrate-resistant acid phosphatase staining and western blotting. Furthermore, we examined the impact of SZW on osteoclastogenesis in vitro using receptor activator of nuclear factor kappa-B ligand (RANKL). Finally, we explored the regulatory effects of SZW on osteoclast autophagy and the AMPK pathway. KEY FINDINGS: The results demonstrated that high-dose SZW reversed changes in bone density parameters caused by OVX, including bone volume (BV), BV/total volume, trabecular number, and trabecular spacing (P = 0.0007, 0.0035, 0.0114, and 0.0182, respectively), and stimulated the formation of bone trabeculae in mice (P < 0.0001). Furthermore, SZW suppressed osteoclast formation in mice with OVX and inhibited osteoclast formation induced by RANKL. Mechanistically, SZW inhibited osteoclast precursor cell autophagy through the AMPK pathway. CONCLUSIONS: SZW effectively inhibited the autophagy of osteoclast precursors by regulating the AMPK pathway, thereby exerting anti-osteoclastogenic effects and serving as an alternative therapy for OP.


Osteoclasts , Osteoporosis , Female , Mice , Animals , Humans , Osteoclasts/metabolism , Osteogenesis , AMP-Activated Protein Kinases/metabolism , X-Ray Microtomography , Osteoporosis/drug therapy , Osteoporosis/metabolism , Signal Transduction , Autophagy , RANK Ligand/metabolism , RANK Ligand/pharmacology , RANK Ligand/therapeutic use , Ovariectomy , Cell Differentiation
11.
Knee ; 47: 43-52, 2024 Mar.
Article En | MEDLINE | ID: mdl-38199041

PURPOSE: The present study was designed to investigate the precise procedure and effectiveness of percutaneous minimally invasive fixation assisted by TiRobot in managing AO/OTA type 41B2 tibial plateau fracture to provide an alternative solution for clinical application. METHODS: In total, 10 participants with AO/OTA type 41B2 tibial plateau fractures diagnosed by preoperative imaging examinations were enrolled in this study between May 2019 and May 2022. They were 5 males and 5 females, with an average age of 45.6 ± 11.3 years old (range 27-62 years old). All of them had closed fractures, including 6 cases with anterior cruciate ligament (ACL) tibial insertion avulsion fractures, 1 case with medial collateral ligament (MCL) tear, and 4 cases with a lateral meniscus tear. From injury through surgery, the entire time frame was 4.0 ± 1.5 days (range, 2-7 days). Following indirect percutaneous reduction assisted by TiRobot, the Jail method was used to treat all patients with minimally invasive internal fixation. Patients with ligament or meniscus injurieswere treated with arthroscopic surgery in one stage. The standardized functional exercise was performed postoperatively. The knee function was measured using the Hospital for Special Surgery (HSS) score, and the fracture reduction was assessed through the Rasmussen radiology score. RESULTS: All patients were followed up for 12.7 ± 6.8 months (6-24 months).The fracture healing time was 11.8 ± 0.8 weeks (10-13 weeks), and the X-rays revealed satisfactory fracture reduction.The knee joint's Rasmussen score was 17.8 ± 0.4 (in the range of 17-18) a year after the procedure, with 8 patients receiving outstanding ratings and 2 cases receiving satisfactory scores. The HSS score was 93.8 ± 2.3 (range, 89 to 96), of which 10 cases were excellent. The motion range of the kneewas 138.7°±2.7° (range, -5° to 0° to 135°). No adverse effects or serious complications, such as internal fixation failure, postoperative infection, popliteal vascular injury, and common peroneal nerve injury, were observed during the last follow-up visit. CONCLUSIONS: The intelligent assistance and accurate guidance of TiRobot can simplify and standardize procedures of percutaneous minimally invasive fixation in theSchatzker type Ⅲ tibial plateau fracture treatment. This technique increases the precision of indirect percutaneous reduction and screw fixation while minimizing bone grafting.


Bone Screws , Fracture Fixation, Internal , Tibial Fractures , Humans , Male , Female , Middle Aged , Adult , Tibial Fractures/surgery , Fracture Fixation, Internal/methods , Fracture Fixation, Internal/instrumentation , Minimally Invasive Surgical Procedures/methods , Robotic Surgical Procedures/methods , Tibial Plateau Fractures
12.
Chem Commun (Camb) ; 60(4): 420-423, 2024 Jan 04.
Article En | MEDLINE | ID: mdl-38086642

We synthesized a small molecule, DBPTO, and used it as a cathode material in aqueous zinc-ion batteries. DBPTO presented a high reversible capacity of 382 mA h g-1 at 0.05 A g-1 and a long lifespan of over 60 000 cycles. In the same π-conjugated skeleton, DBPTO (containing four CO and two CN groups) shows a narrower energy gap than TAPQ (containing CO and four CN groups), which leads to the superior rate and cycling performance of DBPTO. The mechanism of charge storage of DBPTO also revealed that H+ and Zn2+ coordinated with the CO and CN sites by ex situ structural characterization and DFT calculations. Our results provide new insights into the design of organic cathodes with a high rate capability and long lifespan. Further efforts will focus on a deeper understanding of the charge storage mechanism.

13.
Angew Chem Int Ed Engl ; 63(4): e202316449, 2024 Jan 22.
Article En | MEDLINE | ID: mdl-38059893

Owing to outstanding performances, nickel-based electrocatalysts are commonly used in electrochemical alcohol oxidation reactions (AORs), and the active phase is usually vacancy-rich nickel oxide/hydroxide (NiOx Hy ) species. However, researchers are not aware of the catalytic role of atom vacancy in AORs. Here, we study vacancy-induced catalytic mechanisms for AORs on NiOx Hy species. As to AORs on oxygen-vacancy-poor ß-Ni(OH)2 , the only redox mediator is electrooxidation-induced electrophilic lattice oxygen species, which can only catalyze the dehydrogenation process (e.g., the electrooxidation of primary alcohol to carboxylic acid) instead of the C-C bond cleavage. Hence, vicinal diol electrooxidation reaction involving the C-C bond cleavage is not feasible with oxygen-vacancy-poor ß-Ni(OH)2 . Only through oxygen vacancy-induced adsorbed oxygen-mediated mechanism, can oxygen-vacancy-rich NiOx Hy species catalyze the electrooxidation of vicinal diol to carboxylic acid and formic acid accompanied with the C-C bond cleavage. Crucially, we examine how vacancies and vacancy-induced catalytic mechanisms work during AORs on NiOx Hy species.

14.
Front Aging Neurosci ; 15: 1283243, 2023.
Article En | MEDLINE | ID: mdl-37937119

Background: Mild cognitive impairment (MCI) is a transitory yet reversible stage of dementia. Systematic, scientific and population-wide early screening system for MCI is lacking. This study aimed to construct prediction models using longitudinal data to identify potential MCI patients and explore its critical features among Chinese older adults. Methods: A total of 2,128 participants were selected from wave 5-8 of Chinese Longitudinal Healthy Longevity Study. Cognitive function was measured using the Chinese version of Mini-Mental State Examination. Long- short-term memory (LSTM) and three machine learning techniques, including 8 sociodemographic features and 12 health behavior and health status features, were used to predict individual risk of MCI in the next year. Performances of prediction models were evaluated through receiver operating curve and decision curve analysis. The importance of predictors in prediction models were explored using Shapley Additive explanation (SHAP) model. Results: The area under the curve values of three models were around 0.90 and decision curve analysis indicated that the net benefit of XGboost and Random Forest were approximate when threshold is lower than 0.8. SHAP models showed that age, education, respiratory disease, gastrointestinal ulcer and self-rated health are the five most important predictors of MCI. Conclusion: This screening method of MCI, combining LSTM and machine learning, successfully predicted the risk of MCI using longitudinal datasets, and enables health care providers to implement early intervention to delay the process from MCI to dementia, reducing the incidence and treatment cost of dementia ultimately.

15.
Angew Chem Int Ed Engl ; 62(49): e202313954, 2023 Dec 04.
Article En | MEDLINE | ID: mdl-37867149

Due to the robust oxidation conditions in strong acid oxygen evolution reaction (OER), developing an OER electrocatalyst with high efficiency remains challenging in polymer electrolyte membrane (PEM) water electrolyzer. Recent theoretical research suggested that reducing the coordination number of Ir-O is feasible to reduce the energy barrier of the rate-determination step, potentially accelerating the OER. Inspired by this, we experimentally verified the Ir-O coordination number's role at model catalysts, then synthesized low-coordinated IrOx nanoparticles toward a durable PEM water electrolyzer. We first conducted model studies on commercial rutile-IrO2 using plasma-based defect engineering. The combined in situ X-ray absorption spectroscopy (XAS) analysis and computational studies clarify why the decreased coordination numbers increase catalytic activity. Next, under the model studies' guidelines, we explored a low-coordinated Ir-based catalyst with a lower overpotential of 231 mV@10 mA cm-2 accompanied by long durability (100 h) in an acidic OER. Finally, the assembled PEM water electrolyzer delivers a low voltage (1.72 V@1 A cm-2 ) as well as excellent stability exceeding 1200 h (@1 A cm-2 ) without obvious decay. This work provides a unique insight into the role of coordination numbers, paving the way for designing Ir-based catalysts for PEM water electrolyzers.

16.
Article En | MEDLINE | ID: mdl-37751350

Prompt tuning has achieved great success in various sentence-level classification tasks by using elaborated label word mappings and prompt templates. However, for solving token-level classification tasks, e.g., named entity recognition (NER), previous research, which utilizes N-gram traversal for prompting all spans with all possible entity types, is time-consuming. To this end, we propose a novel prompt-based contrastive learning method for few-shot NER without template construction and label word mappings. First, we leverage external knowledge to initialize semantic anchors for each entity type. These anchors are simply appended with input sentence embeddings as template-free prompts (TFPs). Then, the prompts and sentence embeddings are in-context optimized with our proposed semantic-enhanced contrastive loss. Our proposed loss function enables contrastive learning in few-shot scenarios without requiring a significant number of negative samples. Moreover, it effectively addresses the issue of conventional contrastive learning, where negative instances with similar semantics are erroneously pushed apart in natural language processing (NLP)-related tasks. We examine our method in label extension (LE), domain-adaption (DA), and low-resource generalization evaluation tasks with six public datasets and different settings, achieving state-of-the-art (SOTA) results in most cases.

17.
Chem Asian J ; 18(20): e202300679, 2023 Oct 17.
Article En | MEDLINE | ID: mdl-37695094

Single-atom catalysts (SACs) have the unique coordination environment and electronic structure due to the quantum size effect, which plays an essential role in facilitating catalytic reactions. However, due to the limited understanding of the formation mechanism of single atoms, achieving the modulation of the local atomic structure of SACs is still difficult and challenging. Herein, we have prepared a series of Ni SACs loaded on nitrogen-doped carbon substrates with different parameters using a dissolution-and-carbonization method to systematically investigate the effect of temperature on the structure of the SACs. The results of characterization and electrochemical measurements are analyzed to reveal the uniform law between temperature and the metal loading, bond length, coordination number, valence state and CO2 reduction performance, showing the feasibility of controlling the structure of SACs through temperature to regulate the catalytic performance. This is important for the understanding of catalytic reaction mechanisms and the design of efficient catalysts.

18.
Adv Mater ; 35(42): e2305659, 2023 Oct.
Article En | MEDLINE | ID: mdl-37620729

Oxygen evolution reaction (OER) plays a key role in proton exchange membrane water electrolysis (PEMWE), yet the electrocatalysts still suffer from the disadvantages of low activity and poor stability in acidic conditions. Here, a new class of CdRu2 IrOx nanoframes with distorted structure for acidic OER is successfully fabricated. Impressively, CdRu2 IrOx displays an ultralow overpotential of 189 mV and an ultralong stability of 1500 h at 10 mA cm⁻2 toward OER in 0.5 M H2 SO4 . Moreover, a PEMWE using the distorted CdRu2 IrOx can be steadily operated at 0.1 A cm⁻2 for 90 h. Microstructural analyses and X-ray absorption spectroscopy (XAS) demonstrate that the synergy between Ru and Ir in CdRu2 IrOx induces the distortion of Ru-O, Ir-O, and Ru-M (M = Ru, Ir) bonds. In situ XAS indicates that the applied potential leads to the deformation octahedral structure of RuOx /IrOx and the formation of stable Ru5+ species for OER. Theoretical calculations also reveal that the distorted structures can reduce the energy barrier of rate-limiting step during OER. This work provides an efficient strategy for constructing structural distortion to achieve significant enhancement on the activity and stability of OER catalysts.

19.
ACS Appl Mater Interfaces ; 15(36): 42868-42880, 2023 Sep 13.
Article En | MEDLINE | ID: mdl-37647236

Usually, most studies focus on toxic gas and photosensors by using electrospinning and metal oxide polycrystalline SnO2 nanofibers (PNFs), while fewer studies discuss cell-material interactions and photoelectric effect. In this work, the controllable surface morphology and oxygen defect (VO) structure properties were provided to show the opportunity of metal oxide PNFs to convert photoenergy into bio-energy for bio-material applications. Using the photobiomodulation effect of defect-rich polycrystalline SnO2 nanofibers (PNFs) is the main idea to modulate the cell-material interactions, such as adhesion, growth direction, and reactive oxygen species (ROS) density. The VO structures, including out-of-plane oxygen defects (op-VO), bridge oxygen defects (b-VO), and in-plane oxygen defects (ip-VO), were studied using synchrotron analysis to investigate the electron transfer between the VO structures and conduction bands. These intragrain VO structures can be treated as generation-recombination centers, which can convert various photoenergies (365-520 nm) into different current levels that form distinct surface potential levels; this is referred to as the photoelectric effect. PNF conductivity was enhanced 53.6-fold by enlarging the grain size (410 nm2) by increasing the annealing temperature, which can improve the photoelectric effect. In vitro removal of reactive oxygen species (ROS) can be achieved by using the photoelectric effect of PNFs. Also, the viability and shape of human bone marrow mesenchymal stem cells (hMSCs-BM) were also influenced significantly by the photobiomodulation effect. The cell damage and survival rate can be prevented and enhanced by using PNFs; metal oxide nanofibers are no longer only environmental sensors but can also be a bio-material to convert the photoenergy into bio-energy for biomedical science applications.

20.
Phytomedicine ; 118: 154967, 2023 Sep.
Article En | MEDLINE | ID: mdl-37490802

BACKGROUND: Guizhi Shaoyao Zhimu decoction, a traditional Chinese medicine formula used empirically for the treatment of rheumatoid arthritis (RA), has been shown to alleviate bone destruction in rats with collagen-induced arthritis (CIA). PURPOSE: The aim of this study is to characterize the effects of Guizhi Shaoyao Zhimu granules (GSZGs) on bone destruction in RA and the underlying mechanism. STUDY DESIGN: A CIA arthritis model using DBA/1 mice. The animals were divided into a normal group; CIA model group; low, medium, and high-dose GSZG groups (3, 6, and 9 g/kg/day); and a methotrexate group (1.14 mg/kg/w). In vitro, a cytokine induced osteoclastogenesis model was established. METHODS: After 28 days of treatment, the paw volume was measured, bone destruction was examined by micro-CT, and the generation of osteoclasts in bone tissue was evaluated via tartrate-resistant acid phosphatase (TRAP) staining. Furthermore, the inhibitory effect and underlying mechanism of action of GSZG on RANKL-induced osteoclastogenesis were investigated in vitro. RESULTS: The in vivo analyses demonstrated that the paw volume and degree of bone erosion of mice in the medium- and high-dose GSZG groups were significantly decreased compared to the CIA model group. In addition, GSZG treatment suppressed the excessive generation of osteoclasts in the bone tissue of CIA mice. In vitro, GSZG inhibited RANKL-induced osteoclastogenesis and osteoclast-mediated bone resorption. Specifically, it only inhibited the generation of osteoclast precursors (OCPs); it had no significant effect on the fusion of OCPs or maturation of osteoclasts. Finally, we showed that the inhibitory effect of GSZG on osteoclastogenesis was related to the promotion of PTEN-induced kinase protein 1 (PINK1)/Parkin pathway-mediated mitophagy of osteoclast precursors, which was verified using a PINK1 knockdown small interfering RNA in OCPs. CONCLUSION: These findings indicate that GSZG is a candidate for the treatment of bone destruction in RA and provide a more detailed elucidation of the mechanism of GSZG anti-RA bone erosion, i.e., inhibition of the ROS/NF-κB axis through the PINK1/Parkin-mediated mitochondrial autophagic pathway to inhibit osteoclast precursor production, compared to the published literature.


Arthritis, Experimental , Arthritis, Rheumatoid , Bone Resorption , Mice , Rats , Animals , Osteoclasts/metabolism , Osteogenesis , Arthritis, Experimental/drug therapy , Arthritis, Experimental/metabolism , Mitophagy , Mice, Inbred DBA , Arthritis, Rheumatoid/drug therapy , Bone Resorption/drug therapy , Bone Resorption/metabolism , Protein Kinases/metabolism , RANK Ligand/pharmacology , RANK Ligand/metabolism
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