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Proton ceramic fuel cells (PCFCs) are gaining attention due to their high energy conversion efficiency. However, the development of PCFCs is hindered by the lack of efficient and robust cathode materials. This article proposes a solution by introducing certain cationic deficiency into the Ba 0.9 La 0.1 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ (BLCFN) cathode matrix, which results in abundance of oxygen vacancies as well as enhanced proton defects. Consequently, the catalytic activity and hydration activity of the BLCFN oxygen electrode are improved during the reduction reaction process. Specifically, the polarization impedance (R p) of the (Ba 0.9 La 0.1) 0.95 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ (BL95CFN) decreases by 20% compared to the pristine BLCFN, reaching 0.12 Ω·cm2 at 700 °C in air. The R p of BL95CFN decreases by 12% in a steam environment of 20 vol%. This enhancement is attributed to the higher concentration of oxygen vacancies, which leads to an improved proton diffusion rate and hydration performance. The peak power density of the anode-supported BL95CFN | BZCYYb | BZCYYb-NiO single cell reaches 641 mW cm−2 at 700 °C, and the performance of this single cell remains stable for nearly 100 h. These findings highlight the vital role of adjusting oxygen vacancy and proton diffusion, providing a feasible strategy for improving the performance and stability of PCFC cathode materials. • An A-site deficiency engineered Ba 0.9 La 0.1 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ cathode is proposed. • A-site deficiency greatly enhanced ORR activity of Ba 0.9 La 0.1 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ. • Oxygen vacancy by introducing cationic defects, enhances catalytic activity and hydration reaction activity. • (Ba 0.9 La 0.1) 0.95 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ cathode showed good long-term stability. [ABSTRACT FROM AUTHOR]

Protonic ceramic fuel cells (PCFCs) have been the focus of research due to their advantageous properties compared to oxygen ion-conducting solid oxide fuel cells (SOFCs). However, the biggest obstacles to the development of PCFC are the lower proton conductivity and the poor stability in high concentration steam environment. Herein, we report a novel composite cathode with surface reconfiguration, comprised of BaCoO 3-δ (BCO) nanoparticles by water-induced precipitation and Ba 0.9 Pr 0.1 Co 0.7 Fe 0.2 Y 0.1 O 3-δ (BPCFY) substrate with e−/O2−/H+ triple conducting behavior, exhibiting high catalytic activity towards oxygen reduction reaction (ORR) and stability in high steam concentration. With wet hydrogen (3 vol% H 2 O) as fuel and wet air (3 vol% H 2 O) as oxidant, the peak power density of NiO-BZCYYb|BZCYYb|BPCFY single cell reaches 750 mW•cm−2 at 700 °C, approximately 25 % higher than that using dry air at cathode side. Such improvement performance can be attributed to the precipitation of BaCoO 3-δ nanoparticles that increase the active adsorption sites as well as the increased oxygen vacancy concentration by Pr doping in BaCo 0.7 Fe 0.2 Y 0.1 O 3-δ , which synergistically expand the triple phase boundary and facilitate ions migration. This work provided a promising approach to enhance the catalytic activity of PCFC at lower temperatures while also improving its tolerance to steam. • Pr-doping promotes BaCoO 3 nanoparticles precipitation after steam treatment. • Pr-doping improves the ions diffusion process. • The exsolved BaCoO 3 nanoparticles facilitate the gas exchange process. • The composite cathode showed desirable tolerance for steam and carbon dioxide. [ABSTRACT FROM AUTHOR]

Zhenwu Decoction (ZWD) is a traditional Chinese medicine (TCM) formula which has wide scope of indications related to Yang deficiency and dampness retention in TCM syndrome. Cardiac hypertrophy can induce similar symptoms and signs to the clinical features of Yang deficiency and dampness retention syndrome. ZWD can increase the left ventricular ejection fraction, reduce cardiac hypertrophy of patients with chronic heart failure. However, its underlying pharmacological mechanism remains unclear. The study aimed to confirm the protective effects of ZWD on cardiac hypertrophy and explore the underlying mechanisms. The potential targets and pathways of ZWD in cardiac hypertrophy were highlighted by network pharmacology and validated by mechanistic and functional studies. Our network pharmacology analysis suggests that the protective effects of ZWD on cardiac hypertrophy are related to cyclic guanosine monophosphate (cGMP) - protein kinase G (PKG) pathway. Subsequent animal studies showed that ZWD significantly ameliorated cardiac function decline, cardiac hypertrophy, cardiac fibrosis and cardiomyocyte apoptosis. To explore the underlying mechanisms of action, we performed Western blotting, immunohistochemical analysis, and detection of inflammatory response and oxidative stress. Our results showed that ZWD activated the soluble guanylate cyclase (sGC) - cGMP - PKG signaling pathway. The sGC inhibitor ODQ that blocks the sGC-cGMP-PKG signaling pathway in zebrafish abolished the protective effects of ZWD, suggesting sGC-cGMP-PKG is the main signaling pathway mediates the protective effect of ZWD in cardiac hypertrophy. In addition, three major ingredients from ZWD, poricoic acid C, hederagenin and dehydrotumulosic acid, showed a high binding energy with prototype sGC. ZWD reduces oxidative stress and inflammation and exerts cardioprotective effects by activating the sGC-cGMP-PKG signaling pathway. [Display omitted] • Zhenwu Decoction (ZWD) exhibited significant therapeutic effects on cardiac hypertrophy. • ZWD restored the sGC-cGMP-PKG signaling pathway suppressed by cardiac hypertrophy. • Inhibition of the sGC-cGMP-PKG signaling pathway abolished the protective effect of ZWD on cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

Highly efficient and stable cathodes are significantly vital for solid oxide fuel cells (SOFCs). However, one of key impediment to the cathode development is the undesirable oxygen reduction activity and stability with exposure upon steam. Herein, we present a novel nanoparticles-decorated cathode, comprised of O2−/e−/H+ triple-conducting K+-doped BaCo 0.7 Fe 0.2 Y 0.1 O 3-δ (Ba 0.9 K 0.1 Co 0.7 Fe 0.2 Y 0.1 O 3-δ , BKCFY) matrix oxide and the mixed O2−/e− conducting nanoparticles of BaCoO 3-δ (BCO) through water-mediated exsolution process, exhibiting high activity and robust stability with exposure upon the steam. The cathode shows a low polarization resistance of 0.048 Ω cm2 at 700 °C when exposed upon humid air with 3% H 2 O, approximately 24% lower than that in dry air (0.065 Ω cm2 at 700 °C). Such improvement is mainly ascribed to the exsolved BaCoO 3- δ nanoparticles decorated on the porous BKCFY, which enlarged the triple phase boundary for oxygen reduction reaction. The increased oxygen vacancy concentration through K doping can accelerate the Ba and Co ions segregation to form BaCoO 3-δ with exposure upon the wet condition. Furthermore, K+ dopant with higher basicity than Ba2+ is beneficial for hydration behavior, which effectively promotes the catalytic activity under the water vapor. Moreover, the exsolved BaCoO 3-δ nanoparticles are socketed on the BKCFY matrix oxide, which ensures high stability for this hybrid cathode operated at 700 °C. The findings provide a promising approach to design the triple-conducting cathode for solid oxide fuel cells via water-mediated exsolution, which can also be applied for solid oxide electrolysis cells and membrane reactors. [Display omitted] [ABSTRACT FROM AUTHOR]

Symmetrical solid oxide fuel cells (SSOFCs) with identical anode and cathode have many benefits compared with traditional SOFCs. However, it is still a challenge to find high performance electrode materials with excellent catalytic activity and preferable stability under both reducing and oxidizing atmosphere. Here, a novel Ba 0.9 La 0.1 Co 0.7 Fe 0.2 Nb 0.1 O 3-δ (BLCFN) perovskite electrode has been developed as promising symmetrical electrode material for SSOFCs. The A-site non-stoichiometry introduced in BLCFN simultaneously enhances both the cathode and anode electrocatalytic performance. The cathode polarization resistance of BLCFN with 5% deficiency is decreased by 28.6% to 0.05 Ω·cm2 at 750°C in air, which can be mainly attributed to the increase of oxygen vacancy concentration via partial ionic defect. The BLCFN anode polarization resistance is reduced by 42.1% to 0.11 Ω·cm2 at 750°C in 5% H 2 /N 2. The promoted hydrogen oxidation reaction activity of BLCFN is related to the exsolved homogeneous Co-Fe nanoparticles from BL95CFN substrate in reducing atmosphere. The full cell with BL95CFN symmetrical electrodes displays high redox stability through reversing the flow of wet hydrogen and ambient air. Additionally, this SSOFCs with strong anchor characteristic of exsolved Co-Fe nanoparticles shows excellent coking-tolerance using methane fuel compared with traditional Ni-SDC anode. This work provides a potential way towards the development of high-performance, excellent redox-stable and coking-tolerant SSOFCs. [ABSTRACT FROM AUTHOR]

The significant challenges facing the development of the cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs) are the poor oxygen reduction reaction (ORR) activity as well as the CO 2 poisoning issues. Herein, an La/Nb co-doped perovskite Ba 0.9 La 0.1 Co 0.7 Fe 0.2 Nb 0.1 O 3- δ (BLCFN) has been developed as a promising cathode for IT-SOFCs. The polarization resistance of BLCFN cathode is 0.073 Ω cm2 at 700 °C air. This remarkable improved ORR activity can be attributed to the increased oxygen vacancies caused by the introduction of La3+ and Nb5+ ions. Furthermore, the collaboration introduction of La3+ and Nb5+ ions greatly reduce the alkalinity of the BLCFN electrode, bringing excellent CO 2 -tolerance for BLCFN cathode. No carbonate is yielded on the surface of the BLCFN cathode. The improvement on CO 2 -tolerance for these cathodes is largely attributed to the introduction of Nb5+ ions, which have higher acidity and more powerful M − O bond, and the introduction of La3+ can improve the ORR activity of the material on this basis. The co-doping of La/Nb elements furtherly stabilizes the lattice structure. Overall, the high ORR activity and CO 2 -tolerance of the cathode manifest a bright application prospect for BLCFN cathode in SOFCs and other membrane reactors. [Display omitted] • A more stable cubic structure is achieved by La/Nb co-doping. • La/Nb co-doping improves the oxygen reduction reaction activity. • BLCFN cathode material exhibits superior resistance towards CO 2 poisoning. • A peak power density of 812 mW cm−2 is achieved at 700 °C with BLCFN cathode. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a common progressive neurodegenerative disease characterized by memory impairments, and there is no effective therapy. Neural stem/progenitor cell (NSPC) has emerged as potential novel therapy for AD, and we aim to explore whether neural stem/progenitor cell therapy was effective for rodent models of AD. Methods: We searched PubMed, Embase, Cochrane Library and Web of Science up to December 6, 2022. The outcomes included cognitive function, pathological features and BDNF. The GetData Graph Digitizer software (version 2.26) was applied to extract numerical values, and RevMan 5.3 and Stata 16 were used to analyze data. The SYRCLE risk of bias tool was used to assess study quality. Results: We evaluated 22 mice studies and 8 rat studies. Compared to control groups, cognitive function of NSPC groups of both mice studies (SMD = − 1.96, 95% CI − 2.47 to − 1.45, I2 = 75%, P < 0.00001) and rat studies (SMD = − 1.35, 95% CI − 2.11 to − 0.59, I2 = 77%, P = 0.0005) was apparently improved. In mice studies, NSPC group has lower Aβ deposition (SMD = − 0.96, 95% CI − 1.40 to − 0.52, P < 0.0001) and p-tau level (SMD = − 4.94, 95% CI − 7.29 to − 2.95, P < 0.0001), higher synaptic density (SMD = 2.02, 95% CI 0.50–3.55, P = 0.009) and BDNF (SMD = 1.69, 95% CI 0.61–2.77, P = 0.002). Combined with nanoformulation (SMD = − 1.29, 95% CI − 2.26 to − 0.32, I2 = 65%, P = 0.009) and genetically modified (SMD = − 1.29, 95% CI − 1.92 to − 0.66, I2 = 60%, P < 0.0001) could improve the effect of NSPC. In addition, both xenogeneic and allogeneic transplant of NSPC could reverse the cognitive impairment of AD animal models. Conclusions: Our results suggested that NSPC therapy could improve the cognitive function and slow down the progression of AD. Due to the limitations of models, more animal trials and clinical trials are needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biotin-decorated celastrol-loaded ZIF-8 nanoparticles (CEL@ZIF-8@BIO) exhibit excellent water solubility and a high release rate in acidic environments. • CEL@ZIF-8@BIO effectively inhibits tumour proliferation and alleviates the toxicity of celastrol. • The mechanism of CEL@ZIF-8@BIO in anti-colorectal cancer is related to ferroptosis. Celastrol (CEL) has garnered significant interest for its anti-tumour properties and potential for colorectal cancer (CRC) treatment. However, its clinical use is constrained by its limited bioavailability and potential toxicity. Herein, a biotin-decorated CEL nano-drug delivery system using a zeolitic imidazolate framework (ZIF-8) as a carrier was synthesized, named CEL@ZIF-8@BIO. It exhibits excellent water solubility, efficient loading of CEL, and a high release rate in acidic environments. In vitro experiments demonstrated that CEL@ZIF-8@BIO inhibited proliferation, induced cell cycle arrest in G0/G1 phase, increased ROS production and reduced mitochondrial membrane potential in CRC cells. RNA-Seq analysis indicated that the anticancer mechanism of CEL@ZIF-8@BIO may be linked to ferroptosis as indicated by a significant increase in Fe2+ levels, oxidative stress, lipid peroxidation, and mitochondrial dysfunction in CRC cells. Furthermore, these effects could be reversed by ferroptosis inhibitor. In vivo research revealed that CEL@ZIF-8@BIO significantly inhibited the growth of CRC tumours and reduced the toxicity associated with CEL treatment. Taken together, the CEL@ZIF-8@BIO nano-drug delivery system shows great promise for CRC therapy due to its improved efficacy and reduced toxicity. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the metabolites of rotundic acid after oral administration to rats and compare the similarities with its biotransformation by Syncephalastrum racemosum AS 3.264 using ultra-high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry. A total of fourteen metabolites were determined based on the mass spectrometry and chromatographic behaviors, among which eleven (M1–M3, M7–M14) and six (M2, M4–M8) metabolites were identified in rats and S. racemosum , respectively. Three identical metabolites (M2, M7 and M8) were found in rats and S. racemosum , indicating that there were metabolic similarities. Moreover, to confirm the results of mass spectrometry, three (M2, M4 and M7) metabolites were obtained by the means of amplifying incubation and their structures were determined by various spectroscopic analyses, and M4 was proved to be a previously undescribed compound. This results showed that in vitro assisted preparation by microbial transformation is a feasible and effective method of obtaining metabolites which are in low amounts and difficult to be prepared in vivo . [ABSTRACT FROM AUTHOR]

The association between schizophrenia (SZ) and uric acid (UA) levels has been suggested for many years, but without solid evidence. Therefore, we conducted a systematic review and meta-analysis of all case-control studies examining the serum and plasma UA levels in SZ subjects in comparison to those in healthy controls. Relevant studies published before October 29, 2018, were searched in the main electronic databases, and 17 studies were finally included into the meta-analysis after screening with the criteria. Our results revealed that there were no statistically significant differences of the UA levels between SZ subjects and healthy controls. Further subgroup analyses of the antipsychotic status reported the same finding. Subgroup analyses of clinical status showed that UA levels were decreased in subjects with first episode psychosis (FEP). The subgroup analyses of gender and ethnicity demonstrated that UA levels were decreased in male subjects and in Americans with SZ. Overall, these findings strengthen the clinical evidence that FEP is accompanied by increased oxidative stress response. Reduced UA levels may be a potential risk factor for SZ in male and in the Americans. However, whether there is a causal relationship between the reduced UA levels and the development of SZ deserves further investigation. [ABSTRACT FROM AUTHOR]