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1.
Int J Mol Sci ; 25(12)2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38928117

ABSTRACT

Cla4, an orthologous p21-activated kinase crucial for non-entomopathogenic fungal lifestyles, has two paralogs (Cla4A/B) functionally unknown in hypocrealean entomopathogens. Here, we report a regulatory role of Cla4A in gene expression networks of Beauveria bassiana required for asexual and entomopathogenic lifecycles while Cla4B is functionally redundant. The deletion of cla4A resulted in severe growth defects, reduced stress tolerance, delayed conidiation, altered conidiation mode, impaired conidial quality, and abolished pathogenicity through cuticular penetration, contrasting with no phenotype affected by cla4B deletion. In ∆cla4A, 5288 dysregulated genes were associated with phenotypic defects, which were restored by targeted gene complementation. Among those, 3699 genes were downregulated, including more than 1300 abolished at the transcriptomic level. Hundreds of those downregulated genes were involved in the regulation of transcription, translation, and post-translational modifications and the organization and function of the nuclear chromosome, chromatin, and protein-DNA complex. DNA-binding elements in promoter regions of 130 dysregulated genes were predicted to be targeted by Cla4A domains. Samples of purified Cla4A extract were proven to bind promoter DNAs of 12 predicted genes involved in multiple stress-responsive pathways. Therefore, Cla4A acts as a novel regulator of genomic expression and stability and mediates gene expression networks required for insect-pathogenic fungal adaptations to the host and environment.


Subject(s)
Beauveria , Fungal Proteins , Gene Expression Regulation, Fungal , Gene Regulatory Networks , Beauveria/genetics , Beauveria/pathogenicity , Fungal Proteins/genetics , Fungal Proteins/metabolism , Animals , Insecta/microbiology , Spores, Fungal/genetics , Promoter Regions, Genetic
2.
J Fungi (Basel) ; 10(6)2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38921406

ABSTRACT

In budding yeast, Rad5 and Rad7-Rad16 play respective roles in the error-free post-replication repair and nucleotide excision repair of ultraviolet-induced DNA damage; however, their homologs have not yet been studied in non-yeast fungi. In the fungus Beauveria bassiana, a deficiency in the Rad7 homolog, Rad5 ortholog and two Rad16 paralogs (Rad16A/B) instituted an ability to help the insect-pathogenic fungus to recover from solar UVB damage through photoreactivation. The fungal lifecycle-related phenotypes were not altered in the absence of rad5, rad16A or rad16B, while severe defects in growth and conidiation were caused by the double deletion of rad16A and rad16B. Compared with the wild-type and complemented strains, the mutants showed differentially reduced activities regarding the resilience of UVB-impaired conidia at 25 °C through a 12-h incubation in a regime of visible light plus dark (L/D 3:9 h or 5:7 h for photoreactivation) or of full darkness (dark reactivation) mimicking a natural nighttime. The estimates of the median lethal UVB dose LD50 from the dark and L/D treatments revealed greater activities of Rad5 and Rad16B than of Rad16A and additive activities of Rad16A and Rad16B in either NER-dependent dark reactivation or photorepair-dependent photoreactivation. However, their dark reactivation activities were limited to recovering low UVB dose-impaired conidia but were unable to recover conidia impaired by sublethal and lethal UVB doses as did their photoreactivation activities at L/D 3:9 or 5:7, unless the night/dark time was doubled or further prolonged. Therefore, the anti-UV effects of Rad5, Rad16A and Rad16B in B. bassiana depend primarily on photoreactivation and are mechanistically distinct from those for their yeast homologs.

3.
Nat Commun ; 15(1): 5157, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886340

ABSTRACT

The eukaryotic asparagine (N)-linked glycan is pre-assembled as a fourteen-sugar oligosaccharide on a lipid carrier in the endoplasmic reticulum (ER). Seven sugars are first added to dolichol pyrophosphate (PP-Dol) on the cytoplasmic face of the ER, generating Man5GlcNAc2-PP-Dol (M5GN2-PP-Dol). M5GN2-PP-Dol is then flipped across the bilayer into the lumen by an ER translocator. Genetic studies identified Rft1 as the M5GN2-PP-Dol flippase in vivo but are at odds with biochemical data suggesting Rft1 is dispensable for flipping in vitro. Thus, the question of whether Rft1 plays a direct or an indirect role during M5GN2-PP-Dol translocation has been controversial for over two decades. We describe a completely reconstituted in vitro assay for M5GN2-PP-Dol translocation and demonstrate that purified Rft1 catalyzes the translocation of M5GN2-PP-Dol across the lipid bilayer. These data, combined with in vitro results demonstrating substrate selectivity and rft1∆ phenotypes, confirm the molecular identity of Rft1 as the M5GN2-PP-Dol ER flippase.


Subject(s)
Endoplasmic Reticulum , Endoplasmic Reticulum/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Biological Transport , Oligosaccharides/metabolism , Dolichol Phosphates/metabolism , Dolichol Phosphates/genetics , Lipid Bilayers/metabolism , Phospholipid Transfer Proteins/metabolism , Phospholipid Transfer Proteins/genetics , Intracellular Membranes/metabolism , Lipopolysaccharides
4.
Osteoporos Int ; 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844560

ABSTRACT

We conducted a retrospective cohort analysis to examine the association between hemoglobin (Hb) levels and refracture risk in elderly patients with osteoporotic fractures (OPFs). Our findings suggest a nonlinear relationship exists in females, and females with Hb levels below 10.7 g/dL may be at a higher risk of refracture. INTRODUCTION: Hematopoiesis and bone health have a reciprocal influence on each other. Nevertheless, there is a scarcity of in-depth research on the association between Hb levels and the occurrence of fractures. The present research aimed to investigate the correlation between Hb levels and the rate of refracture within 5 years among individuals with OPFs. METHODS: A retrospective cohort analysis was undertaken between 2017 and 2022. The study included 1906 individuals who were inhabitants of Kunshan and were over 60 years old. These individuals had experienced an OPF between January 1, 2017, and July 27, 2022, resulting in their hospitalization. Cox proportional hazard regression models were used to evaluate the risk of refracture within 5 years based on the Hb levels acquired during the admission examination, with consideration for sex differences. A nonlinear relationship was identified using smoothed curve fitting and threshold analysis. Kaplan-Meier curves were used to compare refracture rates between patients with low and high Hb levels. RESULTS: Elderly female patients with OPFs and lower Hb levels exhibited a significantly higher risk of a 5-year refracture. Conversely, no significant associations were observed between the two variables in male patients. A nonlinear correlation was found between Hb levels and the probability of refracture in females, with a turning point identified at 10.7 g/dL of Hb levels. A strong negative association was observed with the five-year refracture rate when Hb levels fell below 10.7 g/dL (hazard ratio (HR) = 0.63; 95% confidence interval (CI) 0.48 to 0.83; P-value = 0.0008). This finding suggests that for every 1 g/dL increase in Hb below 10.7 g/dL, the risk of refracture reduced by 37%. However, no statistically significant association was observed when Hb levels were above 10.7 g/dL. CONCLUSIONS: The findings demonstrated a significant negative correlation between Hb levels and the likelihood of refracture in elderly female patients with OPFs and suggested that elderly females with recent OPFs and Hb levels below 10.7 g/dL may be at a higher risk of refracture. Additionally, the Hb levels can serve as an indicator of bone fragility in elderly female patients with OPFs. These findings highlight the importance of monitoring Hb levels as a part of comprehensive management strategies to both assess skeletal health and prevent refractures in this population.

5.
Harmful Algae ; 136: 102652, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38876530

ABSTRACT

Microplastics are well known as contaminants in marine environments. With the development of biofilms, most microplastics will eventually sink and deposit in benthic environment. However, little research has been done on benthic toxic dinoflagellates, and the effects of microplastics on benthic dinoflagellates are unknown. Prorocentrum lima is a cosmopolitan toxic benthic dinoflagellate, which can produce a range of polyether metabolites, such as diarrhetic shellfish poisoning (DSP) toxins. In order to explore the impact of microplastics on marine benthic dinoflagellates, in this paper, we studied the effects of polystyrene (PS) on the growth and toxin production of P. lima. The molecular response of P. lima to microplastic stress was analyzed by transcriptomics. We selected 100 nm, 10 µm and 100 µm PS, and set three concentrations of 1 mg L-1, 10 mg L-1 and 100 mg L-1. The results showed that PS exposure had limited effects on cell growth, but increased the OA and extracellular polysaccharide content at high concentrations. After exposure to PS MPs, genes associated with DSP toxins synthesis, carbohydrate synthesis and energy metabolism, such as glycolysis, TCA cycle and pyruvate metabolism, were significantly up-regulated. We speculated that after exposure to microplastics, P. lima may increase the synthesis of DSP toxins and extracellular polysaccharides, improve the level of energy metabolism and gene expression of ABC transporter, thereby protecting algal cells from damage. Our findings provide new insights into the effects of microplastics on toxic benthic dinoflagellates.


Subject(s)
Dinoflagellida , Microplastics , Polystyrenes , Dinoflagellida/drug effects , Dinoflagellida/genetics , Dinoflagellida/physiology , Microplastics/toxicity , Marine Toxins , Water Pollutants, Chemical/toxicity , Transcriptome/drug effects
6.
J Vis Exp ; (208)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38912770

ABSTRACT

Transgenesis in Drosophila is an essential approach to studying gene function at the organism level. Embryo microinjection is a crucial step for the construction of transgenic flies. Microinjection requires some types of equipment, including a microinjector, a micromanipulator, an inverted microscope, and a stereo microscope. Plasmids isolated with a plasmid miniprep kit are qualified for microinjection. Embryos at the pre-blastoderm or syncytial blastoderm stage, where nuclei share a common cytoplasm, are subjected to microinjection. A cell strainer eases the process of dechorionating embryos. The optimal time for dechorionation and desiccation of embryos needs to be determined experimentally. To increase the efficiency of embryo microinjection, needles prepared by a puller need to be beveled by a needle grinder. In the process of grinding needles, we utilize a foot air pump with a pressure gauge to avoid the capillary effect of the needle tip. We routinely inject 120-140 embryos for each plasmid and obtain at least one transgenic line for around 85% of plasmids. This article takes the phiC31 integrase-mediated transgenesis in Drosophila as an example and presents a detailed protocol for embryo microinjection for transgenesis in Drosophila.


Subject(s)
Drosophila , Gene Transfer Techniques , Microinjections , Animals , Microinjections/methods , Gene Transfer Techniques/instrumentation , Drosophila/genetics , Drosophila/embryology , Plasmids/genetics , Plasmids/administration & dosage , Embryo, Nonmammalian , Animals, Genetically Modified , Integrases/genetics
7.
Biochem Biophys Res Commun ; 724: 150225, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38852503

ABSTRACT

Data acquisition for transcriptomic studies used to be the bottleneck in the transcriptomic analytical pipeline. However, recent developments in transcriptome profiling technologies have increased researchers' ability to obtain data, resulting in a shift in focus to data analysis. Incorporating machine learning to traditional analytical methods allows the possibility of handling larger volumes of complex data more efficiently. Many bioinformaticians, especially those unfamiliar with ML in the study of human transcriptomics and complex biological systems, face a significant barrier stemming from their limited awareness of the current landscape of ML utilisation in this field. To address this gap, this review endeavours to introduce those individuals to the general types of ML, followed by a comprehensive range of more specific techniques, demonstrated through examples of their incorporation into analytical pipelines for human transcriptome investigations. Important computational aspects such as data pre-processing, task formulation, results (performance of ML models), and validation methods are encompassed. In hope of better practical relevance, there is a strong focus on studies published within the last five years, almost exclusively examining human transcriptomes, with outcomes compared with standard non-ML tools.


Subject(s)
Gene Expression Profiling , Machine Learning , Transcriptome , Humans , Gene Expression Profiling/methods , Computational Biology/methods
8.
J Vis Exp ; (207)2024 May 17.
Article in English | MEDLINE | ID: mdl-38829124

ABSTRACT

Functional genomics screening offers a powerful approach to probe gene function and relies on the construction of genome-wide plasmid libraries. Conventional approaches for plasmid library construction are time-consuming and laborious. Therefore, we recently developed a simple and efficient method, CRISPR-based modular assembly (CRISPRmass), for high-throughput construction of a genome-wide upstream activating sequence-complementary DNA/open reading frame (UAS-cDNA/ORF) plasmid library. Here, we present a protocol for CRISPRmass, taking as an example the construction of a GAL4/UAS-based UAS-cDNA/ORF plasmid library. The protocol includes massively parallel two-step test tube reactions followed by bacterial transformation. The first step is to linearize the existing complementary DNA (cDNA) or open reading frame (ORF) cDNA or ORF library plasmids by cutting the shared upstream vector sequences adjacent to the 5' end of cDNAs or ORFs using CRISPR/Cas9 together with single guide RNA (sgRNA), and the second step is to insert a UAS module into the linearized cDNA or ORF plasmids using a single step reaction. CRISPRmass allows the simple, fast, efficient, and cost-effective construction of various plasmid libraries. The UAS-cDNA/ORF plasmid library can be utilized for gain-of-function screening in cultured cells and for constructing a genome-wide transgenic UAS-cDNA/ORF library in Drosophila.


Subject(s)
CRISPR-Cas Systems , Gene Library , Open Reading Frames , Plasmids , Plasmids/genetics , Animals , CRISPR-Cas Systems/genetics , Open Reading Frames/genetics , DNA, Complementary/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Drosophila melanogaster/genetics
9.
Int J Antimicrob Agents ; : 107252, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38908534

ABSTRACT

OBJECTIVES: The study aimed to develop a genotypic antimicrobial resistance testing method for Klebsiella pneumoniae using metagenomic sequencing data. METHODS: We utilized Lasso regression on assembled genomes to identify genetic resistance determinants for six antibiotics (Gentamicin, Tobramycin, Imipenem, Meropenem, Ceftazidime, Trimethoprim/Sulfamethoxazole). The genetic features were weighted, grouped into clusters to establish classifier models. Origin species of detected antibiotic resistant gene (ARG) was determined by novel strategy integrating "possible species", "gene copy number calculation" and "species-specific kmers". The performance of the method was evaluated on retrospective case studies. RESULTS: Our study employed machine learning on 3928 K. pneumoniae isolates, yielding stable models with AUCs > 0.9 for various antibiotics. GenseqAMR, a read-based software, exhibited high accuracy (AUC 0.926-0.956) for short-read datasets. The integration of a species-specific kmer strategy significantly improved ARG-species attribution to an average accuracy of 96.67%. In a retrospective study of 191 K. pneumoniae-positive clinical specimens (0.68%-93.39% genome coverage), GenseqAMR predicted 84.23% of AST results on average. It demonstrated 88.76%-96.26% accuracy for resistance prediction, offering genotypic AST results with a shorter turnaround time (mean ± SD: 18.34 ± 0.87 hours) than traditional culture-based AST (60.15 ± 21.58 hours). Furthermore, a retrospective clinical case study involving 63 cases showed that GenseqAMR could lead to changes in clinical treatment for 24 (38.10%) cases, with 95.83% (23/24) of these changes deemed beneficial. CONCLUSIONS: In conclusion, GenseqAMR is a promising tool for quick and accurate AMR prediction in Klebsiella pneumoniae, with the potential to improve patient outcomes through timely adjustments in antibiotic treatment.

10.
J Am Heart Assoc ; 13(10): e028006, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38726894

ABSTRACT

BACKGROUND: S100a8/9 (S100 calcium binding protein a8/9) belongs to the S100 family and has gained a lot of interest as a critical regulator of inflammatory response. Our previous study found that S100a8/9 homolog promoted aortic valve sclerosis in mice with chronic kidney disease. However, the role of S100a8/9 in pressure overload-induced cardiac hypertrophy remains unclear. The present study was to explore the role of S100a8/9 in cardiac hypertrophy. METHODS AND RESULTS: Cardiomyocyte-specific S100a9 loss or gain of function was achieved using an adeno-associated virus system, and the model of cardiac hypertrophy was established by aortic banding-induced pressure overload. The results indicate that S100a8/9 expression was increased in response to pressure overload. S100a9 deficiency alleviated pressure overload-induced hypertrophic response, whereas S100a9 overexpression accelerated cardiac hypertrophy. S100a9-overexpressed mice showed increased FGF23 (fibroblast growth factor 23) expression in the hearts after exposure to pressure overload, which activated calcineurin/NFAT (nuclear factor of activated T cells) signaling in cardiac myocytes and thus promoted hypertrophic response. A specific antibody that blocks FGFR4 (FGF receptor 4) largely abolished the prohypertrophic response of S100a9 in mice. CONCLUSIONS: In conclusion, S100a8/9 promoted the development of cardiac hypertrophy in mice. Targeting S100a8/9 may be a promising therapeutic approach to treat cardiac hypertrophy.


Subject(s)
Calgranulin A , Calgranulin B , Disease Models, Animal , Fibroblast Growth Factor-23 , Fibroblast Growth Factors , Myocytes, Cardiac , NFATC Transcription Factors , Up-Regulation , Animals , Calgranulin A/metabolism , Calgranulin A/genetics , Fibroblast Growth Factors/metabolism , Fibroblast Growth Factors/genetics , Calgranulin B/metabolism , Calgranulin B/genetics , NFATC Transcription Factors/metabolism , NFATC Transcription Factors/genetics , Fibroblast Growth Factor-23/metabolism , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Signal Transduction , Cardiomegaly/metabolism , Cardiomegaly/pathology , Mice, Inbred C57BL , Male , Mice, Knockout , Calcineurin/metabolism , Mice , Hypertrophy, Left Ventricular/metabolism , Hypertrophy, Left Ventricular/physiopathology , Hypertrophy, Left Ventricular/genetics , Hypertrophy, Left Ventricular/pathology , Ventricular Remodeling
11.
Angew Chem Int Ed Engl ; : e202406515, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38803131

ABSTRACT

Transformation of carbon dioxide and nitrate ions into urea offers an attractive route for both nitrogen fertilizer production and environmental remediation. However, achieving this transformation under mild conditions remains challenging. Herein, we report an efficient photoelectrochemical method for urea synthesis by co-reduction of carbon dioxide and nitrate ion over a Cu2O photocathode, delivering urea formation rate of 29.71±2.20 µmol g-1 h-1 and Faradaic efficiency (FE) of 12.90±1.15 % at low external potential (-0.017 V vs. reversible hydrogen electrode). Experimental data combined with theoretical calculations suggest that the adsorbed CO* and NO2* species are the key intermediates, and associated C-N coupling is the rate-determining step. This work demonstrates that Cu2O is an efficient catalyst to drive co-reduction of CO2 and NO3- to urea under light irradiation with low external potential, showing great opportunity of photoelectrocatalysis as a sustainable tool for value-added chemical synthesis.

12.
J Clin Gastroenterol ; 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38607993

ABSTRACT

OBJECTIVE: To investigate the efficacy and safety of vonoprazan based bismuth-containing quadruple therapy (VBCQ) in eradicating Helicobacter pylori (Hp). MATERIALS AND METHODS: The VBCQ and the proton pump inhibitor-based bismuth-containing quadruple regimen (PBCQ) were compared by retrieving relevant studies in Pubmed, Embase, Cochrane Library, CNKI, and Wanfang data. Combined analysis was performed with risk ratio (RR) and 95% CI as effect values. RESULTS: A total of 10 studies were enrolled, including 7 randomized controlled trials and 3 cohort studies. In intention-to-treat analysis, the eradication rate of VBCQ (89.24%, 1103/1236) was significantly higher than that of PBCQ (84.03%, 1021/1215), with RR = 1.06 (95% CI: 1.03~1.10). In per-protocol analysis, the eradication rates of VBCQ and PBCQ were 92.94% (895/963) and 87.82% (829/944), respectively, with a significant difference (RR = 1.06, 95% CI: 1.03~1.09). Subgroup analysis of study design types shared similar results. VBCQ and PBCQ showed an incidence of adverse reactions of 37.30% (304/815) and 34.94% (282/807), respectively. Significant differences were not found between the two groups (RR = 1.07, 95% CI: 0.96-1.19), nor in subgroup analysis. The good compliance rates in VBCQ and PBCQ groups were 94.32% (216/229) and 95.13% (215/226), respectively, with no significant difference (RR = 0.99, 95% CI: 0.95~1.04). CONCLUSION: VBCQ has a higher eradication rate on Hp than PBCQ, while its adverse reactions and compliance are similar to PBCQ. However, we conservatively believe that in Hp eradication, the VBCQ is not inferior to PBCQ because of the small absolute difference.

13.
Opt Express ; 32(6): 9958-9966, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38571219

ABSTRACT

In this study, a three-dimensional (3D) laser micromachining system with an integrated sub-100 nm resolution in-situ measurement system was proposed. The system used the same femtosecond laser source for in-situ measurement and machining, avoiding errors between the measurement and the machining positions. It could measure the profile of surfaces with an inclination angle of less than 10°, and the measurement resolution was greater than 100 nm. Consequently, the precise and stable movement of the laser focus could be controlled, enabling highly stable 3D micromachining. The results showed that needed patterns could be machined on continuous surfaces using the proposed system. The proposed machining system is of great significance for broadening the application scenarios of laser machining.

14.
J Am Chem Soc ; 146(18): 12864-12876, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38670931

ABSTRACT

Deep-ultraviolet (DUV) light sources are technologically highly important, but DUV light-emitting materials are extremely rare; AlN and its alloys are the only materials known so far, significantly limiting the chemical and structural spaces for materials design. Here, we perform a high-throughput computational search for DUV light emitters based on a set of carefully designed screening criteria relating to the sophisticated electronic structure. In this way, we successfully identify 5 promising material candidates that exhibit comparable or higher radiative recombination coefficients than AlN, including BeGeN2, Mg3NF3, KCaBr3, KHS, and RbHS. Further, we unveil the unique features in the atomic and electronic structures of DUV light emitters and elucidate the fundamental genetic reasons why DUV light emitters are extremely rare. Our study not only guides the design and synthesis of efficient DUV light emitters but also establishes the genetic nature of ultrawide-band-gap semiconductors in general.

15.
Drug Chem Toxicol ; : 1-15, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38647114

ABSTRACT

Methylmercury (MeHg) exposure can cause nerve damage and mitochondrial dysfunction. Mitochondrial dysfunction is mainly mediated by mitochondrial biogenesis and mitochondrial dynamics disorders. Quercetin (QE) plays an important role in activating silencing information regulator 2 related enzyme 1 (SIRT1), and SIRT1 activates peroxisome-proliferator-activated receptor-γ co-activator 1α (PGC-1α), which can regulate mitochondrial biogenesis and mitochondrial dynamics. The main purpose of this study was to explore the alleviating effects of QE on MeHg-induced nerve damage and mitochondrial dysfunction. The results showed that QE could reduce the excessive production of reactive oxygen species (ROS) and the loss of membrane potential induced by MeHg. Meanwhile, QE activated SIRT1 activity and SIRT1/PGC-1α signaling pathway, improved mitochondrial biogenesis and fusion and reduced mitochondrial fission. In summary, we hypothesized that QE prevents MeHg-induced mitochondrial dysfunction by activating SIRT1/PGC-1α signaling pathway.

16.
JACS Au ; 4(4): 1509-1520, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38665658

ABSTRACT

The precise control of spin states in transition metal (TM)-based single-atom catalysts (SACs) is crucial for advancing the functionality of electrocatalysts, yet it presents significant scientific challenges. Using density functional theory (DFT) calculations, we propose a novel mechanism to precisely modulate the spin state of the surface-adsorbed Fe atom on the MoS2 bilayer. This is achieved by strategically intercalating a TM atom into the interlayer space of the MoS2 bilayer. Our results show that these strategically intercalated TM atoms can induce a substantial interfacial charge polarization, thereby effectively controlling the charge transfer and spin polarization on the surface Fe site. In particular, by varying the identity of the intercalated TM atoms and their vacancy filling site, a continuous modulation of the spin states of the surface Fe site from low to medium to high can be achieved, which can be accurately described using descriptors composed of readily accessible intrinsic properties of materials. Using the electrochemical dinitrogen reduction reaction (eNRR) as a prototypical reaction, we discovered a universal volcano-like relation between the tuned spin and the catalytic activity of Fe-based SACs. This finding contrasts with the linear scaling relationships commonly seen in traditional studies and offers a robust new approach to modulating the activity of SACs through interfacial engineering.

17.
Redox Biol ; 72: 103130, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38522110

ABSTRACT

Redox-responsive hydropersulfide prodrugs are designed to enable a more controllable and efficient hydropersulfide (RSSH) supply and to thoroughly explore their biological and therapeutic applications in oxidative damage. To obtain novel activation patterns triggered by redox signaling, we focused on NAD(P)H: quinone acceptor oxidoreductase 1 (NQO1), a canonical antioxidant enzyme, and designed NQO1-activated RSSH prodrugs. We also performed a head-to-head comparison of two mainstream structural scaffolds with solid quantitative analysis of prodrugs, RSSH, and metabolic by-products by LC-MS/MS, confirming that the perthiocarbamate scaffold was more effective in intracellular prodrug uptake and RSSH production. The prodrug was highly potent in oxidative stress management against cisplatin-induced nephrotoxicity. Strikingly, this prodrug possessed potential feedback activation properties by which the delivered RSSH can further escalate the prodrug activation via NQO1 upregulation. Our strategy pushed RSSH prodrugs one step further in the pursuit of efficient release in biological matrices and improved druggability against oxidative stress.


Subject(s)
NAD(P)H Dehydrogenase (Quinone) , Oxidation-Reduction , Oxidative Stress , Prodrugs , Sulfides , Prodrugs/pharmacology , Prodrugs/chemistry , Oxidative Stress/drug effects , NAD(P)H Dehydrogenase (Quinone)/metabolism , Oxidation-Reduction/drug effects , Sulfides/chemistry , Sulfides/pharmacology , Humans , Animals , Tandem Mass Spectrometry , Cisplatin/pharmacology , Antioxidants/pharmacology , Antioxidants/chemistry , Mice
18.
J Phys Chem Lett ; 15(7): 2006-2014, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38349852

ABSTRACT

Improving the efficiency of the oxygen evolution reaction (OER) is crucial for advancing sustainable and environmentally friendly hydrogen energy. Layered double hydroxides (LDHs) have emerged as promising electrocatalysts for the OER. However, a thorough understanding of the impact of structural disorder and defects on the catalytic activity of LDHs remains limited. In this work, a series of NiAl-LDH models are systematically constructed, and their OER performance is rigorously screened through theoretical density functional theory. The acquired results unequivocally reveal that the energy increase induced by structural disorder is effectively counteracted at the defect surface, indicating the coexistence of defects and disorder. Notably, it is ascertained that the simultaneous presence of defects and disorder synergistically augments the catalytic activity of LDHs in the context of the OER. These theoretical findings offer valuable insights into the design of highly efficient OER catalysts while also shedding light on the efficacy of LDH electrocatalysts.

19.
Ann Clin Transl Neurol ; 11(4): 905-915, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38311755

ABSTRACT

OBJECTIVE: This study aims to explore the frequency and influencing factors of asymptomatic spinal lesions (ASLs) and their impact on subsequent relapses in patients with AQP4-IgG-positive NMOSD (AQP4-NMOSD) in a real-world setting. METHODS: We retrospectively reviewed clinical information and spinal MRI data from AQP4-NMOSD patients who had at least one spinal cord MRI during their follow-ups. Kaplan-Meier curves and Cox proportional hazards models were employed to ascertain potential predictors of remission ASLs and to investigate factors associated with subsequent relapses. RESULTS: In this study, we included 129 patients with AQP4-NMOSD and reviewed 173 spinal MRIs during attacks and 89 spinal MRIs during remission. Among these, 6 ASLs (3.5%) were identified during acute attacks, while 8 ASLs (9%) were found during remission. Remission ASLs were linked to the use of immunosuppressive agents, particularly conventional ones, whereas no patients using rituximab developed ASLs (p = 0.005). Kaplan-Meier curve analysis indicated that patients with ASLs had a significantly higher relapse risk (HR = 4.658, 95% CI: 1.519-14.285, p = 0.007) compared to those without. Additionally, the use of mycophenolate mofetil (HR = 0.027, 95% CI: 0.003-0.260, p = 0.002) and rituximab (HR = 0.035, 95% CI: 0.006-0.203, p < 0.001) significantly reduced the relapse risk. However, after accounting for other factors, the presence of ASLs did not exhibit a significant impact on subsequent relapses (HR = 2.297, 95% CI: 0.652-8.085, p = 0.195). INTERPRETATION: ASLs may be observed in patients with AQP4-NMOSD. The presence of ASLs may signify an underlying inflammatory activity due to insufficient immunotherapy. The administration of immunosuppressive agents plays a key role in the presence of remission ASLs and the likelihood of subsequent relapses.


Subject(s)
Neuromyelitis Optica , Humans , Neuromyelitis Optica/drug therapy , Cohort Studies , Aquaporin 4 , Rituximab/therapeutic use , Retrospective Studies , Immunosuppressive Agents/therapeutic use , Recurrence , Immunoglobulin G
20.
Dalton Trans ; 53(4): 1691-1697, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38167732

ABSTRACT

Lead-based two-dimensional organic-inorganic hybrid perovskites (2D HOIPs) are popular materials with various optical properties, which can be tuned through metal ion doping. Due to the size and valence misfit, metal ion dopants in 2D lead-based HOIPs are still limited. In this work, Mn2+, Sb3+ and Bi3+ are doped into 2D (HDA)2PbBr4 (HDA = protonated dopamine) successfully. As a result, the dopants in 2D (HDA)2PbBr4 can induce their characteristic optical spectra, which is studied at different temperatures and excitation powers. The temperature-dependent energy transfer in the Mn-doped sample has been clarified, in which abnormal phenomena including negative thermal quenching have been observed. In addition, the dopant ions can impact the phase transition temperatures of the samples, especially lowering their crystallization temperatures greatly. The mussel-inspired organic cation, feasible metal ion regulation, and superior stability provide (HDA)2PbBr4 potential for further applications.

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