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1.
Int J Biol Sci ; 20(7): 2763-2778, 2024.
Article in English | MEDLINE | ID: mdl-38725845

ABSTRACT

Dysregulation of the aldehyde dehydrogenase (ALDH) family has been implicated in various pathological conditions, including cancer. However, a systematic evaluation of ALDH alterations and their therapeutic relevance in hepatocellular carcinoma (HCC) remains lacking. Herein, we found that 15 of 19 ALDHs were transcriptionally dysregulated in HCC tissues compared to normal liver tissues. A four gene signature, including ALDH2, ALDH5A1, ALDH6A1, and ALDH8A1, robustly predicted prognosis and defined a high-risk subgroup exhibiting immunosuppressive features like regulatory T cell (Tregs) infiltration. Single-cell profiling revealed selective overexpression of tumor necrosis factor receptor superfamily member 18 (TNFRSF18) on Tregs, upregulated in high-risk HCC patients. We identified ALDH2 as a tumor suppressor in HCC, with three novel phosphorylation sites mediated by protein kinase C zeta that enhanced enzymatic activity. Mechanistically, ALDH2 suppressed Tregs differentiation by inhibiting ß-catenin/TGF-ß1 signaling in HCC. Collectively, our integrated multi-omics analysis defines an ALDH-Tregs-TNFRSF18 axis that contributes to HCC pathogenesis and represents potential therapeutic targets for this aggressive malignancy.


Subject(s)
Aldehyde Dehydrogenase, Mitochondrial , Carcinoma, Hepatocellular , Liver Neoplasms , T-Lymphocytes, Regulatory , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/immunology , Liver Neoplasms/genetics , Humans , Aldehyde Dehydrogenase, Mitochondrial/metabolism , Aldehyde Dehydrogenase, Mitochondrial/genetics , T-Lymphocytes, Regulatory/metabolism , T-Lymphocytes, Regulatory/immunology , Tumor Microenvironment , Aldehyde Dehydrogenase/metabolism , Aldehyde Dehydrogenase/genetics , Animals , Cell Line, Tumor , Male , Mice , Multiomics
2.
Biotechnol Lett ; 2024 May 11.
Article in English | MEDLINE | ID: mdl-38733437

ABSTRACT

Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM-1 s-1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM-1 s-1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.

3.
Nat Commun ; 15(1): 3961, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38729932

ABSTRACT

Mechanically interlocked molecules (MIMs) including famous catenanes show switchable physical properties and attract continuous research interest due to their potential application in molecular devices. The advantages of using spin crossover (SCO) materials here are enormous, allowing for control through diverse stimuli and highly specific functions, and enabling the transfer of the internal dynamics of MIMs from solution to solid state, leading to macroscopic applications. Herein, we report the efficient self-assembly of catenated metal-organic frameworks (termed catena-MOFs) induced by stacking interactions, through the combination of rationally selected flexible and conjugated naphthalene diimide-based bis-pyridyl ligand (BPND), [MI(CN)2]- (M = Ag or Au) and Fe2+ in a one-step strategy. The obtained bimetallic Hofmann-type SCO-MOFs [FeII(BPND){Ag(CN)2}2]·3CHCl3 (1Ag) and [FeII(BPND{Au(CN)2}2]·2CHCl3·2H2O (1Au) possess a unique three-dimensional (3D) catena-MOF constructed from the polycatenation of two-dimensional (2D) layers with hxl topology. Both complexes undergo thermal- and light-induced SCO. Significantly, abnormal increases in the maximum emission intensity and dielectric constant can be detected simultaneously with the switching of spin states. This research opens up SCO-actuated bistable MIMs that afford dual functionality of coupled fluorescence emission and dielectricity.

5.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731961

ABSTRACT

Recently, the increase in marine temperatures has become an important global marine environmental issue. The ability of energy supply in marine animals plays a crucial role in avoiding the stress of elevated temperatures. The investigation into anaerobic metabolism, an essential mechanism for regulating energy provision under heat stress, is limited in mollusks. In this study, key enzymes of four anaerobic metabolic pathways were identified in the genome of scallop Chlamys farreri, respectively including five opine dehydrogenases (CfOpDHs), two aspartate aminotransferases (CfASTs) divided into cytoplasmic (CfAST1) and mitochondrial subtype (CfAST2), and two phosphoenolpyruvate carboxykinases (CfPEPCKs) divided into a primitive type (CfPEPCK2) and a cytoplasmic subtype (CfPEPCK1). It was surprising that lactate dehydrogenase (LDH), a key enzyme in the anaerobic metabolism of the glucose-lactate pathway in vertebrates, was absent in the genome of scallops. Phylogenetic analysis verified that CfOpDHs clustered according to the phylogenetic relationships of the organisms rather than substrate specificity. Furthermore, CfOpDHs, CfASTs, and CfPEPCKs displayed distinct expression patterns throughout the developmental process and showed a prominent expression in muscle, foot, kidney, male gonad, and ganglia tissues. Notably, CfASTs displayed the highest level of expression among these genes during the developmental process and in adult tissues. Under heat stress, the expression of CfASTs exhibited a general downregulation trend in the six tissues examined. The expression of CfOpDHs also displayed a downregulation trend in most tissues, except CfOpDH1/3 in striated muscle showing significant up-regulation at some time points. Remarkably, CfPEPCK1 was significantly upregulated in all six tested tissues at almost all time points. Therefore, we speculated that the glucose-succinate pathway, catalyzed by CfPEPCK1, serves as the primary anaerobic metabolic pathway in mollusks experiencing heat stress, with CfOpDH3 catalyzing the glucose-opine pathway in striated muscle as supplementary. Additionally, the high and stable expression level of CfASTs is crucial for the maintenance of the essential functions of aspartate aminotransferase (AST). This study provides a comprehensive and systematic analysis of the key enzymes involved in anaerobic metabolism pathways, which holds significant importance in understanding the mechanism of energy supply in mollusks.


Subject(s)
Glucose , Heat-Shock Response , Pectinidae , Phylogeny , Animals , Pectinidae/metabolism , Pectinidae/genetics , Glucose/metabolism , Heat-Shock Response/physiology , Anaerobiosis , Succinic Acid/metabolism , Metabolic Networks and Pathways , Aspartate Aminotransferases/metabolism , Aspartate Aminotransferases/genetics
6.
Transl Oncol ; 45: 101988, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38733642

ABSTRACT

Radiation is one of the standard therapies for pediatric high-grade glioma (pHGG), of which the prognosis remains poor. To gain an in-depth understanding of biological consequences beyond the classic DNA damage, we treated 9 patient-derived orthotopic xenograft (PDOX) models, including one with DNA mismatch repair (MMR) deficiency, with fractionated radiations (2 Gy/day x 5 days). Extension of survival time was noted in 5 PDOX models (P < 0.05) accompanied by γH2AX positivity in >95 % tumor cells in tumor core and >85 % in the invasive foci as well as ∼30 % apoptotic and mitotic catastrophic cell death. The model with DNA MMR (IC-1406HGG) was the most responsive to radiation with a reduction of Ki-67(+) cells. Altered metabolism, including mitochondria number elevation, COX IV activation and reactive oxygen species accumulation, were detected together with the enrichment of CD133+ tumor cells. The latter was caused by the entry of quiescent G0 cells into cell cycle and the activation of self-renewal (SOX2 and BMI1) and epithelial mesenchymal transition (fibronectin) genes. These novel insights about the cellular and molecular mechanisms of fractionated radiation in vivo should support the development of new radio-sensitizing therapies.

7.
Redox Biol ; 73: 103179, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38733909

ABSTRACT

Increasing evidences demonstrate that environmental stressors are important inducers of acute kidney injury (AKI). This study aimed to investigate the impact of exposure to Cd, an environmental stressor, on renal cell ferroptosis. Transcriptomics analyses showed that arachidonic acid (ARA) metabolic pathway was disrupted in Cd-exposed mouse kidneys. Targeted metabolomics showed that renal oxidized ARA metabolites were increased in Cd-exposed mice. Renal 4-HNE, MDA, and ACSL4, were upregulated in Cd-exposed mouse kidneys. Consistent with animal experiments, the in vitro experiments showed that mitochondrial oxidized lipids were elevated in Cd-exposed HK-2 cells. Ultrastructure showed mitochondrial membrane rupture in Cd-exposed mouse kidneys. Mitochondrial cristae were accordingly reduced in Cd-exposed mouse kidneys. Mitochondrial SIRT3, an NAD+-dependent deacetylase that regulates mitochondrial protein stability, was reduced in Cd-exposed mouse kidneys. Subsequently, mitochondrial GPX4 acetylation was elevated and mitochondrial GPX4 protein was reduced in Cd-exposed mouse kidneys. Interestingly, Cd-induced mitochondrial GPX4 acetylation and renal cell ferroptosis were exacerbated in Sirt3-/- mice. Conversely, Cd-induced mitochondrial oxidized lipids were attenuated in nicotinamide mononucleotide (NMN)-pretreated HK-2 cells. Moreover, Cd-evoked mitochondrial GPX4 acetylation and renal cell ferroptosis were alleviated in NMN-pretreated mouse kidneys. These results suggest that mitochondrial GPX4 acetylation, probably caused by SIRT3 downregulation, is involved in Cd-evoked renal cell ferroptosis.

8.
Int Immunopharmacol ; 134: 112222, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38728881

ABSTRACT

Cardiovascular disease is currently the number one cause of death endangering human health. There is currently a large body of research showing that the development of cardiovascular disease and its complications is often accompanied by inflammatory processes. In recent years, epitranscriptional modifications have been shown to be involved in regulating the pathophysiological development of inflammation in cardiovascular diseases, with 6-methyladenine being one of the most common RNA transcriptional modifications. In this review, we link different cardiovascular diseases, including atherosclerosis, heart failure, myocardial infarction, and myocardial ischemia-reperfusion, with inflammation and describe the regulatory processes involved in RNA methylation. Advances in RNA methylation research have revealed the close relationship between the regulation of transcriptome modifications and inflammation in cardiovascular diseases and brought potential therapeutic targets for disease diagnosis and treatment. At the same time, we also discussed different cell aspects. In addition, in the article we also describe the different application aspects and clinical pathways of RNA methylation therapy. In summary, this article reviews the mechanism, regulation and disease treatment effects of m6A modification on inflammation and inflammatory cells in cardiovascular diseases in recent years. We will discuss issues facing the field and new opportunities that may be the focus of future research.

9.
Biomed J ; : 100732, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38697480

ABSTRACT

BACKGROUND: Electrocardiogram (ECG) abnormalities have demonstrated potential as prognostic indicators of patient survival. However, the traditional statistical approach is constrained by structured data input, limiting its ability to fully leverage the predictive value of ECG data in prognostic modeling. METHODS: This study aims to introduce and evaluate a deep-learning model to simultaneously handle censored data and unstructured ECG data for survival analysis. We herein introduce a novel deep neural network called ECG-surv, which includes a feature extraction neural network and a time-to-event analysis neural network. The proposed model is specifically designed to predict the time to 1-year mortality by extracting and analyzing unique features from 12-lead ECG data. ECG-surv was evaluated using both an independent test set and an external set, which were collected using different ECG devices. RESULTS: The performance of ECG-surv surpassed that of the Cox proportional model, which included demographics and ECG waveform parameters, in predicting 1-year all-cause mortality, with a significantly higher concordance index (C-index) in ECG-surv than in the Cox model using both the independent test set (0.860 [95% CI: 0.859- 0.861] vs. 0.796 [95% CI: 0.791- 0.800]) and the external test set (0.813 [95% CI: 0.807- 0.814] vs. 0.764 [95% CI: 0.755- 0.770]). ECG-surv also demonstrated exceptional predictive ability for cardiovascular death (C-index of 0.891 [95% CI: 0.890- 0.893]), outperforming the Framingham risk Cox model (C-index of 0.734 [95% CI: 0.715-0.752]). CONCLUSION: ECG-surv effectively utilized unstructured ECG data in a survival analysis. It outperformed traditional statistical approaches in predicting 1-year all-cause mortality and cardiovascular death, which makes it a valuable tool for predicting patient survival.

10.
Small Methods ; : e2400224, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38697931

ABSTRACT

The pursuit of high energy densities propels the design of next-generation nickel-based layered oxide cathodes. The utilization of low-cobalt, ultrahigh-nickel layered oxide cathodes, and the extension of operating voltages promise enhanced energy density. However, stability and safety face challenges associated with nickel content, including structural degradation, lattice oxygen evolution, and thermal instability. In this study, a promising strategy of Al and Nb dual-bulk-doping is presented in high-Ni cathode materials of LiNi0.96Co0.04O2 (NC) to stabilize the bulk structure, suppress oxygen release, and attain superior electrochemical performance at high voltages. The introduction of Al and Nb effectively raises the migration energy of Ni2+ into Li sites and stabilizes lattice oxygen through strengthened Al─O and Nb─O bonds. Furthermore, the substitution of high-valence Nb ions reduces the charge depletion of lattice oxygen and induces an ordered microstructure. The Al and Nb dual-bulk-doping strategy mitigates strain and stress associated with the H2↔H3 phase transition, reducing the generation and propagation of microcracks. The resulting Li(Ni0.96Co0.04)0.985Al0.01Nb0.005O2 (NCAN) cathode exhibits superior cycling stability, with a capacity retention of 77.8% after 300 cycles, even when operating at a high-voltage of 4.4 V, outperforming the NC (48.5%). This work provides a promising perspective for developing high-voltage and high-Ni cathode materials.

11.
Commun Biol ; 7(1): 545, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714724

ABSTRACT

CircRNAs are covalently closed, single-stranded RNA that form continuous loops and play a crucial role in the initiation and progression of tumors. Cancer stem cells (CSCs) are indispensable for cancer development; however, the regulation of cancer stem cell-like properties in gastric cancer (GC) and its specific mechanism remain poorly understood. We elucidate the specific role of Circ-0075305 in GC stem cell properties. Circ-0075305 associated with chemotherapy resistance was identified by sequencing GC cells. Subsequent confirmation in both GC tissues and cell lines revealed that patients with high expression of Circ-0075305 had significantly better overall survival (OS) rates than those with low expression, particularly when treated with postoperative adjuvant chemotherapy for GC. In vitro and in vivo experiments confirmed that overexpression of Circ-0075305 can effectively reduce stem cell-like properties and enhance the sensitivity of GC cells to Oxaliplatin compared with the control group. Circ-0075305 promotes RPRD1A expression by acting as a sponge for corresponding miRNAs. The addition of LF3 (a ß-catenin/TCF4 interaction antagonist) confirmed that RPRD1A inhibited the formation of the TCF4-ß-catenin transcription complex through competitive to ß-catenin and suppressed the transcriptional activity of stem cell markers such as SOX9 via the Wnt/ß-catenin signaling pathway. This leads to the downregulation of stem cell-like property-related markers in GC. This study revealed the underlying mechanisms that regulate Circ-0075305 in GCSCs and suggests that its role in reducing ß-catenin signaling may serve as a potential therapeutic candidate.


Subject(s)
Down-Regulation , Gene Expression Regulation, Neoplastic , Neoplastic Stem Cells , RNA, Circular , SOX9 Transcription Factor , Stomach Neoplasms , Transcription Factor 4 , beta Catenin , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Humans , SOX9 Transcription Factor/metabolism , SOX9 Transcription Factor/genetics , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , beta Catenin/metabolism , beta Catenin/genetics , RNA, Circular/genetics , RNA, Circular/metabolism , Transcription Factor 4/genetics , Transcription Factor 4/metabolism , Animals , Mice , Cell Line, Tumor , Mice, Nude , Male , Female , Drug Resistance, Neoplasm/genetics , Mice, Inbred BALB C , Middle Aged
12.
Plants (Basel) ; 13(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38732474

ABSTRACT

Genomic selection (GS) is a marker-based selection method used to improve the genetic gain of quantitative traits in plant breeding. A large number of breeding datasets are available in the soybean database, and the application of these public datasets in GS will improve breeding efficiency and reduce time and cost. However, the most important problem to be solved is how to improve the ability of across-population prediction. The objectives of this study were to perform genomic prediction (GP) and estimate the prediction ability (PA) for seed oil and protein contents in soybean using available public datasets to predict breeding populations in current, ongoing breeding programs. In this study, six public datasets of USDA GRIN soybean germplasm accessions with available phenotypic data of seed oil and protein contents from different experimental populations and their genotypic data of single-nucleotide polymorphisms (SNPs) were used to perform GP and to predict a bi-parent-derived breeding population in our experiment. The average PA was 0.55 and 0.50 for seed oil and protein contents within the bi-parents population according to the within-population prediction; and 0.45 for oil and 0.39 for protein content when the six USDA populations were combined and employed as training sets to predict the bi-parent-derived population. The results showed that four USDA-cultivated populations can be used as a training set individually or combined to predict oil and protein contents in GS when using 800 or more USDA germplasm accessions as a training set. The smaller the genetic distance between training population and testing population, the higher the PA. The PA increased as the population size increased. In across-population prediction, no significant difference was observed in PA for oil and protein content among different models. The PA increased as the SNP number increased until a marker set consisted of 10,000 SNPs. This study provides reasonable suggestions and methods for breeders to utilize public datasets for GS. It will aid breeders in developing GS-assisted breeding strategies to develop elite soybean cultivars with high oil and protein contents.

13.
Article in English | MEDLINE | ID: mdl-38709609

ABSTRACT

Developing a distributed bipartite optimal consensus scheme while ensuring user-predefined performance is essential in practical applications. Existing approaches to this problem typically require a complex controller structure due to adopting an identifier-actor-critic framework and prescribed performance cannot be guaranteed. In this work, an adaptive critic learning (ACL)-based optimal bipartite consensus scheme is developed to bridge the gap. A newly designed error scaling function, which defines the user-predefined settling time and steady accuracy without relying on the initial conditions, is then integrated into a cost function. The backstepping framework combines the ACL and integral reinforcement learning (IRL) algorithm to develop the adaptive optimal bipartite consensus scheme, which contributes a critic-only controller structure by removing the identifier and actor networks in the existing methods. The adaptive law of the critic network is derived by the gradient descent algorithm and experience replay to minimize the IRL-based residual error. It is shown that a compute-saving learning mechanism can achieve the optimal consensus, and the error variables of the closed-loop system are uniformly ultimately bounded (UUB). Besides, in any bounded initial condition, the evolution of bipartite consensus is limited to a user-prescribed boundary under bounded initial conditions. The illustrative simulation results validate the efficacy of the approach.

14.
Foot Ankle Int ; : 10711007241247849, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38721810

ABSTRACT

BACKGROUND: This study evaluates the outcomes of fibular intramedullary nails (IMNs) compared to traditional plates and screws (PS) in the surgical treatment of unstable ankle injuries in patients aged ≥65 years. METHOD: We conducted a retrospective study involving 32 elderly patients with unstable ankle fractures treated with IMNs from 2010 to 2022. A comparison was made with 125 case-control patients treated with PS during the same period. Outcomes compared included postoperative wound and nonwound complications, surgical reduction, union rates, implant removal rates, and the Olerud Molander Ankle Score (OMAS) at a minimum follow-up of 2 years. RESULTS: The IMN group had a higher incidence of high-energy injuries, open fractures, concomitant surgery, and perioperative transfusion requirements than the PS group. Additionally, the IMN group developed fewer wound-related (3.1% vs 20% in the PS group, P = .043) and non-wound-related complications (18.8% vs 39.2% in the PS group, P = .030). Both groups had similar initial weightbearing restrictions, fracture union times, mean OMAS scores, rates of malunion or nonunion, and delayed implant removal times. Notably, there were significant differences in the quality and adequacy of mortise alignment between the groups (good: 53.1% in IMN group vs 79.2% in PS group, fair: 46.9% in IMN group vs 20.8% in PS group, P = .006). CONCLUSION: Although the IMN group had an inferior outcome in the quality and adequacy of mortise reduction compared with the PS group, elderly patients with ankle fractures treated with IMN showed comparable functional outcomes to those treated with PS but with lower complication rates. Future research in this area will provide vital information for developing optimal treatment strategies, thereby improving the overall care of elderly patients with ankle fractures. LEVEL OF EVIDENCE: Level III, case-control study.

15.
Gene ; 920: 148530, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38703870

ABSTRACT

Daruqi is a Traditional Mongolian medicine with anti-inflammatory, anti-bacterial, and immune-regulatory effects. However, the mechanisms of its activity were unclear. In the present study, we confirmed the anti-inflammation effect of Daruqi on inflammation induced by LPS using animal models. Then, THP-1 cells treated with LPS was used as a positive control to explore the effective component of Daruqi on inflammation. We identified that Oxymatrine was the essential effector of Daruqi. Furthermore, the mechanism of Oxymatrine on inflammation was verified through proteomics analyses and validation assays. Our results demonstrated that Oxymatrine significantly reduced the levels of inflammatory cytokine, including IL-8, IL-1α, and IL-1ß, in LPS induced THP-1 cells. Based on tandem mass tag -labeled quantitative proteomics, 428 differentially expressed proteins were screened, involved in TNF signaling pathway, Ferroptosis, IL-17 signaling pathway, etc. Among these differential expressed proteins (DEPs), 23 proteins were verified with parallel reaction monitoring analysis. The results showed that LPS treatment potentiated the protein level of PLEK, ACSL5 and CYBB, which could be reversed by Oxymatrine. By contrast, the protein expression of SPRYD4 and EMR2 was suppressed after LPS treatment, which could be rescued by Oxymatrine. In summary, Oxymatrine has excellent protective effects in LPS induced THP-1 cells. The five proteins, including PLEK, ACSL5, CYBB, SPRYD4 and EMR2, might serve as the targets of Oxymatrine, and as candidates regulating inflammation in future therapies.

16.
Chemphyschem ; : e202300838, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38708615

ABSTRACT

The work function (WF) measurement plays a critical role in engineering energy materials and energy devices. However, the ultra-high vacuum (UHV) environments of photoemission method limit the practical application for absolute work function measurements of materials, especially under complex working conditions. To understand the energy level of materials under complex chemical environments, the in-situ measurements of work function is necessary in complex metal/semiconductor system for various application. In this paper, we describe the utilization of ambient pressure X-ray photoemission spectroscopy (APXPS) with utilization of low photon energy X-ray for absolute WF measurements at BL02B of the Shanghai Synchrotron Radiation Facility. We herein present the WF measurement during oxygen adsorption on Pt(111) and oxidation of Cu(111) in ambient oxygen environment as demonstration of the APXPS capability for WF measurement. After oxygen chemisorption on Pt and formation of Cu2O, the WF will increase. This is due to charge transfer from metal to chemisorbed oxygen atoms. After the formation of bulk Cu2O and CuO, the WF value almost remain at ~5.5 eV. We believe the direct measurement of absolute work function via APXPS could help bridge the gap between the physical properties and the surface chemical species for metal/semiconductor materials.

17.
Adv Healthc Mater ; : e2304576, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38689517

ABSTRACT

Immunotherapeutic effect is restricted by the non-immunogenic tumor phenotype and immunosuppression behaviors of tumor associated macrophages (TAMs). In this work, a drug self-assembly (designated as CeBLZ) is fabricated based on chlorin e6 (Ce6) and BLZ945 to activate photodynamic immunotherapy through tumor immunogenic induction and tumor associated macrophage depletion. It is found that Ce6 tends to assemble with BLZ945 without any drug excipients, which can enhance the cellular uptake, tumor penetration and blood circulation behaviors. The robust photodynamic therapy effect of CeBLZ efficiently suppresses the primary tumor growth and also triggers immunogenic cell death to reverse the non-immunogenic tumor phenotype. Moreover, CeBLZ can deplete TAMs in tumor tissues to reverse the immunosuppression microenvironment, activating abscopal effect for distant tumor inhibition. In vitro and in vivo results confirm the superior anti-tumor effect of CeBLZ with negligible side effect, which might promote the development of sophisticated drug combinations for systematic tumor management. This article is protected by copyright. All rights reserved.

18.
Sensors (Basel) ; 24(9)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38732919

ABSTRACT

Automotive radar is one of the key sensors for intelligent driving. Radar image sequences contain abundant spatial and temporal information, enabling target classification. For existing radar spatiotemporal classifiers, multi-view radar images are usually employed to enhance the information of the target and 3D convolution is employed for spatiotemporal feature extraction. These models consume significant hardware resources and are not applicable to real-time applications. In this paper, RadarTCN, a novel lightweight network, is proposed that achieves high-accuracy online target classification using single-view radar image sequences only. In RadarTCN, 2D convolution and 3D-TCN are employed to extract spatiotemporal features sequentially. To reduce data dimensionality and computational complexity, a multi-layer max pooling down-sampling method is designed in a 2D convolution module. Meanwhile, the 3D-TCN module is improved through residual pruning and causal convolution is introduced for leveraging the performance of online target classification. The experimental results demonstrate that RadarTCN can achieve high-precision online target recognition for both range-angle and range-Doppler map sequences. Compared to the reference models on the CARRADA dataset, RadarTCN exhibits better classification performance, with fewer parameters and lower computational complexity.

19.
J Org Chem ; 2024 May 13.
Article in English | MEDLINE | ID: mdl-38738957

ABSTRACT

A visible-light-enabled photoredox radical cascade cyclization of 2-vinyl benzimidazole derivatives is developed. This chemistry is applicable to a wide range of N-aroyl 2-vinyl benzimidazoles as acceptors, and halo compounds, including alkyl halides, acyl chlorides and sulfonyl chlorides, as radical precursors. The Langlois reagent also serves as an effective partner in this photocatalytic oxidative cascade process. This protocol provides a robust alternative for rendering highly functionalized benzo[4,5]imidazo[1,2-b]isoquinolin-11(6H)-ones.

20.
Int J Biol Macromol ; 267(Pt 1): 131473, 2024 May.
Article in English | MEDLINE | ID: mdl-38614185

ABSTRACT

Actinoplanes utahensis deacylase (AAC)-catalyzed deacylation of echinocandin B (ECB) is a promising method for the synthesis of anidulafungin, the newest of the echinocandin antifungal agents. However, the low activity of AAC significantly limits its practical application. In this work, we have devised a multi-dimensional rational design strategy for AAC, conducting separate analyses on the substrate-binding pocket's volume, curvature, and length. Furthermore, we quantitatively analyzed substrate properties, particularly on hydrophilic and hydrophobic. Accordingly, we tailored the linoleic acid-binding pocket of AAC to accommodate the extended long lipid chain of ECB. By fine-tuning the key residues, the resulting AAC mutants can accommodate the ECB lipid chain with a lower curvature binding pocket. The D53A/I55F/G57M/F154L/Q661L mutant (MT) displayed 331 % higher catalytic efficiency than the wild-type (WT) enzyme. The MT product conversion was 94.6 %, reaching the highest reported level. Utilizing a multi-dimensional rational design for a customized mutation strategy of the substrate-binding pocket is an effective approach to enhance the catalytic efficiency of enzymes in handling complicated substrates.


Subject(s)
Echinocandins , Fungal Proteins , Hydrophobic and Hydrophilic Interactions , Echinocandins/chemistry , Substrate Specificity , Binding Sites , Mutation , Models, Molecular , Amidohydrolases/chemistry , Amidohydrolases/genetics , Amidohydrolases/metabolism , Protein Binding
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