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1.
Cell ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38823389

ABSTRACT

Purine nucleotides are vital for RNA and DNA synthesis, signaling, metabolism, and energy homeostasis. To synthesize purines, cells use two principal routes: the de novo and salvage pathways. Traditionally, it is believed that proliferating cells predominantly rely on de novo synthesis, whereas differentiated tissues favor the salvage pathway. Unexpectedly, we find that adenine and inosine are the most effective circulating precursors for supplying purine nucleotides to tissues and tumors, while hypoxanthine is rapidly catabolized and poorly salvaged in vivo. Quantitative metabolic analysis demonstrates comparative contribution from de novo synthesis and salvage pathways in maintaining purine nucleotide pools in tumors. Notably, feeding mice nucleotides accelerates tumor growth, while inhibiting purine salvage slows down tumor progression, revealing a crucial role of the salvage pathway in tumor metabolism. These findings provide fundamental insights into how normal tissues and tumors maintain purine nucleotides and highlight the significance of purine salvage in cancer.

2.
Dalton Trans ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38828535

ABSTRACT

In aqueous solution, a novel triangle-like tungstovanadate estertin derivative K10H10.5[(W4O15(H2O)2){(SnCH2CH2COO)2(V0.75W10.75/V0.25O39)}{{(SnCH2CH2COO)2(µ-OH)}2(SnCH2CH2COO)(VW10O37)}2]·31H2O ((SnR)8-V3W35, R = CH2CH2COO) was assembled by a conventional synthetic method. (SnR)8-V3W35 is composed of one [VW11O39]7- ({VW11}) and two [VW10O37]9- ({VW10}) units connected by eight [Sn(CH2)2COO]2+ groups and a {W4O19} cluster. Interestingly, there exists a pentagonal bipyramid WO7 polyhedral center surrounded by two SnCO5 and three WO6 octahedra, forming a pentagonal {(WO7)W3(SnR)2} cluster in this polyoxometalate (POM), which is also the first example of a pentagonal structure formed by transition metals (TMs) and main group organometals in the POM family. Furthermore, the structure of this organic-inorganic hybrid POM also exhibits the largest number of organotin groups introduced into the POM system. It was characterized with various physico-chemical and spectroscopic methods, including X-ray single crystal and powder diffraction analysis, 119Sn and 51V NMR, IR, thermal gravimetric analysis (TGA), etc. In addition, the catalytic activity of (SnR)8-V3W35 as a mimic of peroxidase was evaluated using o-phenylenediamine (OPD) as a peroxidase substrate. The major factors influencing the oxidation reaction such as pH, the dosage of (SnR)8-V3W35, and concentrations of OPD and H2O2 were mainly studied. (SnR)8-V3W35 exhibits good peroxidase-like catalytic activity. From another perspective, the successful acquisition of (SnR)8-V3W35 further proves the instability and easy reassembly characteristics of TM-sandwich-type tungstovanadates, which also provides a new assembly strategy for synthesizing POM-estertin derivatives.

3.
Quant Imaging Med Surg ; 14(6): 4054-4066, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38846302

ABSTRACT

Background: Pericoronary adipose tissue (PCAT) is a sensor of vascular inflammation. Elevated PCAT attenuation values indicate the presence of coronary inflammation in patients. However, it is unclear which clinical characteristics are associated with increased PCAT attenuation values in patients without coronary heart disease (CHD). The study aims to investigate the relationship between increased PCAT attenuation values and clinical characteristics of patients without CHD. Methods: We recruited 785 eligible patients without CHD who underwent coronary computed tomographic angiography (CCTA). Clinical data were recorded for each patient, and PCAT attenuation values for the left anterior descending branch (LADPCAT), left circumflex branch (LCXPCAT), and right coronary artery (RCAPCAT) were quantified by CCTA using fully automated software. Univariate and multivariate analyses were performed to identify the associations between different clinical characteristics and elevated LADPCAT, LCXPCAT, and RCAPCAT. Results: Univariate analysis showed body mass index (BMI) to be positively associated with LADPCAT (rs=0.109), LCXPCAT (rs=0.076), and RCAPCAT (rs=0.083). Moreover, the duration of smoking, and drinking was positively associated with LADPCAT (rs=0.099, 0.165). Hyperlipidemia was positively associated with LADPCAT (rs=0.089) and RCAPCAT (rs=0.334), while statin use was negatively associated with RCAPCAT (rs=-0.145). Multivariate analysis showed that the significant determinants of LADPCAT were BMI (ß=0.359, P=0.001), duration of smoking (ß=2.612, P=0.002), drinking (ß=4.106, P<0.001), and hyperlipidemia (ß=1.664, P=0.027). LCXPCAT was associated with BMI (ß=0.218, P=0.024), while RCAPCAT was associated with hyperlipidemia (ß=6.110, P<0.001) and statin use (ß=-3.338, P<0.001). Conclusions: In patients without CHD, the PCAT attenuation values measured using CCTA were associated with various clinical characteristics. LADPCAT was associated with BMI, smoking duration, drinking, and hyperlipidemia. On the other hand, LCXPCAT was associated with BMI, while RCAPCAT was associated with hyperlipidemia and statin use.

4.
Luminescence ; 39(5): e4743, 2024 May.
Article in English | MEDLINE | ID: mdl-38692854

ABSTRACT

A unique luminescent lanthanide metal-organic framework (LnMOF)-based fluorescence detection platform was utilized to achieve sensitive detection of vomitoxin (VT) and oxytetracycline hydrochloride (OTC-HCL) without the use of antibodies or biomolecular modifications. The sensor had a fluorescence quenching constant of 9.74 × 106 M-1 and a low detection limit of 0.68 nM for vomitoxin. Notably, this is the first example of a Tb-MOF sensor for fluorescence detection of vomitoxin. We further investigated its response to two mycotoxins, aflatoxin B1 and ochratoxin A, and found that their Stern-Volmer fluorescence quenching constants were lower than those of VT. In addition, the fluorescence sensor realized sensitive detection of OTC-HCL with a detection limit of 0.039 µM. In conclusion, the method has great potential as a sensitive and simple technique to detect VT and OTC-HCL in water.


Subject(s)
Metal-Organic Frameworks , Oxytetracycline , Terbium , Oxytetracycline/analysis , Oxytetracycline/chemistry , Terbium/chemistry , Metal-Organic Frameworks/chemistry , Spectrometry, Fluorescence , Fluorescent Dyes/chemistry , Limit of Detection , Water/chemistry , Fluorescence , Water Pollutants, Chemical/analysis
5.
Article in English | MEDLINE | ID: mdl-38743893

ABSTRACT

Objective: To explore the differential expression of circLRP6 targeted miR-145 in intracranial aneurysms and its regulation of VSMC biological activity, providing a theoretical foundation for the study of intracranial aneurysm regulation by circLRP6. Methods: Expression levels of circLRP6 and miR-145 mRNA were measured in intracranial aneurysms and superficial temporal arteries. In vitro experiments were conducted using TNF-αstimulated HBVSMCs to evaluate the expression of circLRP6 and miR-145, as well as cell proliferation, apoptosis, migration, and related protein expression. Results: CircLRP6 was low expressed in intracranial aneurysms, and MiR-145 showed a trend of Overexpression; With the increase of circLRP6 expression in intracranial aneurysms, expression of miR-145 decreased. The correlation coefficient, r, was -0.5139; After TNF- α following stimulation, phenotype of VSMCs changed, expression of circLRP6 in cells decreased, and expression of miR-145 increased; CircLRP was successfully overexpressed or knocked out in VSMCs cells; Overexpression of circLRP6 can inhibit concentration expression of miR-145; VSMCs cells showed an increasing trend with time. Overexpression of circLRP6 can inhibit the proliferation process of VSMCs cells, The proliferation activity of cells was enhanced after circLRP6 knockout, and Overexpression of miR-145 could enhance the proliferation activity of VSMCs; Overexpression of circLRP6 could promote apoptosis process of VSMCs, while knockout of circLRP6 and Overexpression of miR-145 could inhibit apoptosis ability of VSMCs; Overexpression of circLRP6 can inhibit migration ability of VSMCs cells. Overexpression of circLRP6 after knockout and miR-145 can enhance the migration ability of cells; After circLRP6 overexpression in VSMCs, α-SMA, SM22α And expression concentration of Calponin protein increased, IL-1ß. The concentration and expression of MMP-2 and MMP-9 protein decreased After knockout of circLRP6 and Overexpression of miR-145, α-SMA, SM22α, And expression concentration of Calponin protein decreased, IL-1ß. The expression of MMP-2 and MMP-9 protein increased (P < .05). Conclusion: CircLRP6 is low expressed in intracranial aneurysms and negatively correlates with miR-145 expression. CircLRP6 may be involved in the development of intracranial aneurysms by influencing VSMC phenotype transformation. CircLRP6 acts as a natural sponge for miR-145, regulating VSMC proliferation, migration, and differentiation and promoting apoptosis, ultimately inhibiting the development of intracranial aneurysms. This study provides a theoretical basis for clinical research on the mechanism of intracranial aneurysms.

6.
Drug Metab Dispos ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38777597

ABSTRACT

Hydrolases represent an essential class of enzymes indispensable for the metabolism of various clinically essential medications. Individuals exhibit marked differences in the expression and activation of hydrolases, resulting in significant variability in the pharmacokinetics (PK) and pharmacodynamics (PD) of drugs metabolized by these enzymes. The regulation of hydrolase expression and activity involves both genetic polymorphisms and nongenetic factors. This review examines the current understanding of genetic and nongenetic regulators of six clinically significant hydrolases, including Carboxylesterase 1 (CES1), Carboxylesterase 2 (CES2), Arylacetamide Deacetylase (AADAC), Paraoxonase 1 (PON1), Paraoxonase 3 (PON3), and Cathepsin A (CTSA). We explore genetic variants linked to the expression and activity of the hydrolases and their effects on the PK and PD of their substrate drugs. Regarding nongenetic regulators, we focus on the inhibitors and inducers of these enzymes. Additionally, we examine the developmental expression patterns and gender differences in the hydrolases when pertinent information was available. Many genetic and nongenetic regulators were found to be associated with the expression and activity of the hydrolases and PK and PD. However, hydrolases remain generally understudied compared to other drug-metabolizing enzymes, such as cytochrome P450s. The clinical significance of genetic and nongenetic regulators has not yet been firmly established for the majority of hydrolases. Comprehending the mechanisms that underpin the regulation of these enzymes holds the potential to refine therapeutic regimens, thereby enhancing the efficacy and safety of drugs metabolized by the hydrolases. Significance Statement Hydrolases play a crucial role in the metabolism of numerous clinically important medications. Genetic polymorphisms and nongenetic regulators can affect hydrolases' expression and activity, consequently influencing the exposure and clinical outcomes of hydrolase substrate drugs. A comprehensive understanding of hydrolase regulation can refine therapeutic regimens, ultimately enhancing the efficacy and safety of drugs metabolized by the enzymes.

7.
Front Microbiol ; 15: 1402319, 2024.
Article in English | MEDLINE | ID: mdl-38808277

ABSTRACT

The toxin-antitoxin (TA) system plays a key role in bacteria escaping antibiotic stress with persistence, however, the mechanisms by which persistence is controlled remain poorly understood. Weissella cibaria, a novel probiotic, can enters a persistent state upon encountering ciprofloxacin stress. Conversely, it resumes from the persistence when ciprofloxacin stress is relieved or removed. Here, it was found that PemIK TA system played a role in transitioning between these two states. And the PemIK was consisted of PemK, an endonuclease toxic to mRNA, and antitoxin PemI which neutralized its toxicity. The PemK specifically cleaved the U↓AUU in mRNA encoding enzymes involved in glycolysis, TCA cycle and respiratory chain pathways. This cleavage event subsequently disrupted the crucial cellular processes such as hydrogen transfer, electron transfer, NADH and FADH2 synthesis, ultimately leading to a decrease in ATP levels and an increase in membrane depolarization and persister frequency. Notably, Arg24 was a critical active residue for PemK, its mutation significantly reduced the mRNA cleavage activity and the adverse effects on metabolism. These insights provided a clue to comprehensively understand the mechanism by which PemIK induced the persistence of W. cibaria to escape ciprofloxacin stress, thereby highlighting another novel aspect PemIK respond for antibiotic stress.

8.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2828-2840, 2024 May.
Article in Chinese | MEDLINE | ID: mdl-38812182

ABSTRACT

The food security of China as a big agricultural country is attracting increasing attention. With the progress in the traditional Chinese medicine industry, Chinese medicinal materials and their preparations have been gradually developed as agents for disease prevention and with antimicrobial and insecticidal functions in agriculture. Promoting pesticide innovation by interdisciplinary integration has become the trend in pesticide research globally. Considering the increasingly important roles of green pesticides from traditional Chinese medicines and artificial intelligence in pest target prediction, this paper proposed an innovative green control strategy in line with the concepts of ecological sustainable development and food security protection. CiteSpace was used for visual analysis of the publications. The results showed that artificial intelligence had been extensively applied in the pesticide field in recent years. This paper explores the application and development of biopesticides for the first time, with focus on the plant-derived pesticides. The thought of traditional Chinese medicine compatibility can be employed to creat a new promosing field: pesticides from traditional Chinese medicine. Moreover, artificial intelligence can be employed to build the formulation system of pesticides from traditional Chinese medicines and the target prediction system of diseases and pests. This study provides new ideas for the future development and market application of biopesticides, aiming to provide more healthy and safe agricultural products for human beings, promote the innovation and development of green pesticides in China, and protect the sustainable development of the environment and ecosystem. This may be the research hotspot and competition point for the green development of the pesticide industry chain in the future.


Subject(s)
Artificial Intelligence , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Pesticides , Pesticides/chemistry , Drugs, Chinese Herbal/chemistry , Animals , Green Chemistry Technology/methods , Humans
9.
PLoS Comput Biol ; 20(5): e1012136, 2024 May.
Article in English | MEDLINE | ID: mdl-38758956

ABSTRACT

In the last few years, Micro-C has shown itself as an improved alternative to Hi-C. It replaced the restriction enzymes in Hi-C assays with micrococcal nuclease (MNase), resulting in capturing nucleosome resolution chromatin interactions. The signal-to-noise improvement of Micro-C allows it to detect more chromatin loops than high-resolution Hi-C. However, compared with massive Hi-C datasets available in the literature, there are only a limited number of Micro-C datasets. To take full advantage of these Hi-C datasets, we present HiC2MicroC, a computational method learning and then predicting Micro-C from Hi-C based on the denoising diffusion probabilistic models (DDPM). We trained our DDPM and other regression models in human foreskin fibroblast (HFFc6) cell line and evaluated these methods in six different cell types at 5-kb and 1-kb resolution. Our evaluations demonstrate that both HiC2MicroC and regression methods can markedly improve Hi-C towards Micro-C, and our DDPM-based HiC2MicroC outperforms regression in various terms. First, HiC2MicroC successfully recovers most of the Micro-C loops even those not detected in Hi-C maps. Second, a majority of the HiC2MicroC-recovered loops anchor CTCF binding sites in a convergent orientation. Third, HiC2MicroC loops share genomic and epigenetic properties with Micro-C loops, including linking promoters and enhancers, and their anchors are enriched for structural proteins (CTCF and cohesin) and histone modifications. Lastly, we find our recovered loops are also consistent with the loops identified from promoter capture Micro-C (PCMicro-C) and Chromatin Interaction Analysis by Paired-End Tag Sequencing (ChIA-PET). Overall, HiC2MicroC is an effective tool for further studying Hi-C data with Micro-C as a template. HiC2MicroC is publicly available at https://github.com/zwang-bioinformatics/HiC2MicroC/.


Subject(s)
Chromatin , Computational Biology , Humans , Chromatin/metabolism , Chromatin/chemistry , Chromatin/genetics , Computational Biology/methods , Cell Line , CCCTC-Binding Factor/metabolism , CCCTC-Binding Factor/genetics , Models, Statistical
10.
Sci Rep ; 14(1): 12251, 2024 05 28.
Article in English | MEDLINE | ID: mdl-38806615

ABSTRACT

Mesenchymal stem cells (MSCs) have demonstrated promising advantages in the therapies of many diseases, while its multi-directional differentiation potential and immunotoxicity are the major concerns hindered their clinical translation. In this study, human umbilical Mesenchymal stem cell (hUC-MSCs) were labeled with a near-infrared fluorescent dye DiR before infused into cynomolgus monkeys, and the amount of hUC-MSCs in the peripheral blood were dynamically estimated from 5 min to 28 days post a single administration at 3 × 106 cells/kg and 2 × 107 cells/kg intravenously. As results, some hUC-MSCs distributed to the whole body within 5 min, while most of the cells accumulate in the lungs along with the systemic blood circulation, and subsequently released into the blood. The toxicity potentials of hUC-MSCs were investigated in another 30 cynomolgus monkeys, and the cells were repeatedly administrated at doses of 3 × 106 cells/kg and 2 × 107 cells/kg for 5 times on a weekly basis, with a recovery period of 1 months. hUC-MSCs showed no obvious toxic effects in cynomolgus monkeys, except xenogeneic immune rejection to human stem cells. Low levels of the hUC-MSC gene were detected in the peripheral blood of a few animals administered 2 × 107 cells/kg at 30 min subsequent to the first and last administration, and there was no significant difference in the copy number of the hUC-MSC gene in the blood samples compared with the first and last administration, indicating that the hUC-MSC was not significantly amplified in vivo, and it its safe in non-human primates. Our study for the first time verified the safety of long-term use of hUC-MSCs in primates. We have pioneered a technology for the real-time detection of hUC-MSCs in peripheral blood and provide dynamicand rapid monitoring of the distribution characteristics of hUC-MSCs in vivo. Here, we provide data supporting the application of such products for clinical treatment and the application of stem cells in major refractory diseases and regenerative medicine.


Subject(s)
Macaca fascicularis , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Umbilical Cord , Animals , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Humans , Umbilical Cord/cytology , Mesenchymal Stem Cell Transplantation/methods , Male , Cell Differentiation , Female
11.
PNAS Nexus ; 3(4): pgae145, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38689706

ABSTRACT

Brain-computer interfaces (BCI) using electroencephalography provide a noninvasive method for users to interact with external devices without the need for muscle activation. While noninvasive BCIs have the potential to improve the quality of lives of healthy and motor-impaired individuals, they currently have limited applications due to inconsistent performance and low degrees of freedom. In this study, we use deep learning (DL)-based decoders for online continuous pursuit (CP), a complex BCI task requiring the user to track an object in 2D space. We developed a labeling system to use CP data for supervised learning, trained DL-based decoders based on two architectures, including a newly proposed adaptation of the PointNet architecture, and evaluated the performance over several online sessions. We rigorously evaluated the DL-based decoders in a total of 28 human participants, and found that the DL-based models improved throughout the sessions as more training data became available and significantly outperformed a traditional BCI decoder by the last session. We also performed additional experiments to test an implementation of transfer learning by pretraining models on data from other subjects, and midsession training to reduce intersession variability. The results from these experiments showed that pretraining did not significantly improve performance, but updating the models' midsession may have some benefit. Overall, these findings support the use of DL-based decoders for improving BCI performance in complex tasks like CP, which can expand the potential applications of BCI devices and help to improve the quality of lives of healthy and motor-impaired individuals.

12.
Gastroenterol Res Pract ; 2024: 1458297, 2024.
Article in English | MEDLINE | ID: mdl-38774521

ABSTRACT

Background: Distal malignant biliary obstruction (DMBO) can result in obstructive jaundice. Endoscopic ultrasound- (EUS-) guided biliary drainage (EUS-BD) has been an alternative for DMBO after failed ERCP. Aim: To compare the efficacy and safety between antegrade and transluminal approaches in patients with unresectable DMBO when ERCP failed. Methods: Patients with DMBO leading to obstructive jaundice after failed ERCP were enrolled in this study. We retrospectively evaluated the safety and efficacy between EUS-guided transluminal stenting (TLS group) and antegrade stenting (AGS group). Results: 82 patients were enrolled, of which 45 patients were in TLS group and 37 in AGS group. There were no statistical differences in the malignancy type, baseline common bile duct diameter, total bilirubin level, reason for EUS-BD, and history of biliary drainage between TLS and AGS groups. The technical success rate was statistically higher in TLS group than in AGS group (97.8 vs. 81.1%, P = 0.031). There were no statistical differences in clinical success rate, procedure-related adverse events, stent migration rate, stent dysfunction rate, reintervention rate, and overall patient survival time between TLS and AGS groups. The median time to stent dysfunction or patient death in TLS and AGS groups was 53 and 81 days, respectively (P = 0.017). Conclusions: Although AGS had a lower technical success rate than TLS, it was superior to TLS in stent patency in patients with DMBO.

13.
Biosens Bioelectron ; 259: 116417, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38795496

ABSTRACT

Assembling functional molecules on the surface of an enzyme electrode is the most basic technique for constructing a biosensor. However, precise control of electron transfer interface or electron mediator on the electrode surface remains a challenge, which is a key step that affects the stability and sensitivity of enzyme-based biosensors. In this study, we propose the use of controllable free radical polymerization to grow stable 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) polymer as electron mediator on enzyme surface for the first time. Through scanning electron microscopy (SEM), Raman spectroscopy, electrode surface coverage measurement, static contact angle (SCA), and a series of electrochemical methods, it has been demonstrated that the TEMPO-based enzyme electrode exhibits a uniform hydrophilic morphology and stable electrochemical performance. Furthermore, the results show that the sensor demonstrates high sensitivity for detecting glucose biomolecules in artificial sweat and serum. Attributing to the quantitative and controllable radical polymerization of TEMPO redox assembled enzyme electrode surface, the as-proposed biosensor providing a use, storage, and inter-batch sensing stability, providing a vital platform for wearable/implantable biochemical sensors.


Subject(s)
Biosensing Techniques , Cyclic N-Oxides , Electrodes , Enzymes, Immobilized , Oxidation-Reduction , Polymerization , Biosensing Techniques/methods , Cyclic N-Oxides/chemistry , Enzymes, Immobilized/chemistry , Electrochemical Techniques/methods , Glucose/analysis , Glucose/chemistry , Glucose Oxidase/chemistry , Humans , Polymers/chemistry
14.
Sci Total Environ ; 938: 173479, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38802005

ABSTRACT

Thermal power plants are significant contributors to nitrogen oxides (NOx), impacting global atmospheric conditions and human health. Satellite observations, known for their continuity and global coverage, have become an effective means of quantifying power plant emissions. Previous studies, often accumulating long temporal data into integrated plumes, resulted in substantial errors in annual emissions at the individual power plant level due to neglecting variations in emissions and diffusion conditions. This study presents, for the first time, the quantification of instantaneous NOx emissions based on single overpass observations from the Tropospheric Monitoring Instrument (TROPOMI) aboard the Sentinel-5 Precursor satellite. By addressing the temporal variability of power plant emissions, it effectively reduces annual estimation errors. Comparative analysis between the Exponentially-Modified Gaussian (EMG) and Gaussian Plume Model (GPM) simulations demonstrates the capability of EMG to provide instantaneous emission estimates based on actual plumes, exhibiting closer proximity to actual monitoring values than GPM. Applying the EMG method, we quantify the instantaneous emission rates of six power plants in the United States. Comparing annual emission estimations at individual power plants with traditional integrated plume results, our method demonstrates a 63.7 % improvement in annual emission estimations. This study offers more detailed data on power plant emissions, providing a new avenue for better understanding the emission behavior of thermal power plants.

15.
Anal Chem ; 96(21): 8586-8593, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38728058

ABSTRACT

Nowadays, signal enhancement is imperative to increase sensitivity of advanced ECL devices for expediting their promising applications in clinic. In this work, photodynamic-assisted electrochemiluminescence (PDECL) device was constructed for precision diagnosis of Parkinson, where an advanced emitter was prepared by electrostatically linking 2,6-dimethyl-8-(3-carboxyphenyl)4,4'-difluoroboradiazene (BET) with 1-butyl-3-methylimidazole tetrafluoroborate ([BMIm][BF4]). Specifically, protoporphyrin IX (PPIX) can trigger the photodynamic reaction under light irradiation with a wavelength of 450 nm to generate lots of singlet oxygen (1O2), showing a 2.43-fold magnification in the ECL responses. Then, the aptamer (Apt) was assembled on the functional BET-[BMIm] for constructing a "signal off" ECL biosensor. Later on, the PPIX was embedded into the G-quadruplex (G4) of the Apt to magnify the ECL signals for bioanalysis of α-synuclein (α-syn) under light excitation. In the optimized surroundings, the resulting PDECL sensor has a broad linear range of 100.0 aM ∼ 10.0 fM and a low limit of detection (LOD) of 63 aM, coupled by differentiating Parkinson patients from normal individuals according to the receiver operating characteristic (ROC) curve analysis of actual blood samples. Such research holds great promise for synthesis of other advanced luminophores, combined with achieving an early clinical diagnosis.


Subject(s)
Boron Compounds , Electrochemical Techniques , Luminescent Measurements , Parkinson Disease , Humans , Parkinson Disease/diagnosis , Parkinson Disease/blood , Boron Compounds/chemistry , Biosensing Techniques/methods , alpha-Synuclein/analysis , alpha-Synuclein/blood , Protoporphyrins/chemistry , Aptamers, Nucleotide/chemistry , Limit of Detection
16.
Nat Commun ; 15(1): 4266, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769298

ABSTRACT

Cancer cells exhibit distinct metabolic activities and nutritional dependencies compared to normal cells. Thus, characterization of nutrient demands by individual tumor types may identify specific vulnerabilities that can be manipulated to target the destruction of cancer cells. We find that MYC-driven liver tumors rely on augmented tryptophan (Trp) uptake, yet Trp utilization to generate metabolites in the kynurenine (Kyn) pathway is reduced. Depriving MYC-driven tumors of Trp through a No-Trp diet not only prevents tumor growth but also restores the transcriptional profile of normal liver cells. Despite Trp starvation, protein synthesis remains unhindered in liver cancer cells. We define a crucial role for the Trp-derived metabolite indole 3-pyruvate (I3P) in liver tumor growth. I3P supplementation effectively restores the growth of liver cancer cells starved of Trp. These findings suggest that I3P is a potential therapeutic target in MYC-driven cancers. Developing methods to target this metabolite represents a potential avenue for liver cancer treatment.


Subject(s)
Carcinogenesis , Indoles , Liver Neoplasms , Proto-Oncogene Proteins c-myc , Tryptophan , Tryptophan/metabolism , Animals , Liver Neoplasms/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Indoles/metabolism , Indoles/pharmacology , Humans , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Mice , Carcinogenesis/metabolism , Carcinogenesis/genetics , Cell Line, Tumor , Kynurenine/metabolism , Mice, Inbred C57BL , Liver/metabolism , Liver/pathology , Male
17.
Expert Opin Drug Metab Toxicol ; 20(5): 377-397, 2024 May.
Article in English | MEDLINE | ID: mdl-38706437

ABSTRACT

INTRODUCTION: Carboxylesterase 1 (CES1) and carboxylesterase 2 (CES2) are among the most abundant hydrolases in humans, catalyzing the metabolism of numerous clinically important medications, such as methylphenidate and clopidogrel. The large interindividual variability in the expression and activity of CES1 and CES2 affects the pharmacokinetics (PK) and pharmacodynamics (PD) of substrate drugs. AREAS COVERED: This review provides an up-to-date overview of CES expression and activity regulations and examines their impact on the PK and PD of CES substrate drugs. The literature search was conducted on PubMed from inception to January 2024. EXPERT OPINION: Current research revealed modest associations of CES genetic polymorphisms with drug exposure and response. Beyond genomic polymorphisms, transcriptional and posttranslational regulations can also significantly affect CES expression and activity and consequently alter PK and PD. Recent advances in plasma biomarkers of drug-metabolizing enzymes encourage the research of plasma protein and metabolite biomarkers for CES1 and CES2, which could lead to the establishment of precision pharmacotherapy regimens for drugs metabolized by CESs. Moreover, our understanding of tissue-specific expression and substrate selectivity of CES1 and CES2 has shed light on improving the design of CES1- and CES2-activated prodrugs.


Subject(s)
Carboxylic Ester Hydrolases , Humans , Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/metabolism , Animals , Polymorphism, Genetic , Pharmaceutical Preparations/metabolism , Prodrugs/pharmacokinetics , Biomarkers/metabolism , Carboxylesterase
18.
Eur J Pharmacol ; 975: 176646, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38762157

ABSTRACT

Severe acute pancreatitis (SAP) is a complicated inflammatory reaction that impacts the pancreas, often resulting in damage to numerous organs. This disorder encompasses a range of processes such as inflammation, oxidative stress, and pancreatitis. The hormone melatonin (MT) is primarily secreted by the pineal gland and plays a crucial role in mitigating inflammation, countering the harmful effects of free radicals, and regulating oxidative stress. The aim of this research was to investigate the potential protective impact and the underlying mechanism of melatonin in mice afflicted with SAP. The biochemical and histological assessments unequivocally demonstrated that melatonin effectively inhibited necrosis, infiltration, edema and cell death in pancreatic tissues, thereby suppressing acute pancreatitis. Notably, melatonin also alleviated the consequent harm to distant organs, notably the lungs, liver, and kidneys. Furthermore, both preventive and therapeutic administration of melatonin prompted nuclear factor E2-related factor 2 (Nrf2) activation followed by Nrf2 target gene expression. Nrf2 initiates the activation of antioxidant genes, thereby providing defense against oxidative stress. Conversely, Nrf2 reduction may contribute to impaired antioxidant protection in SAP. The beneficial impact of Nrf2 on antioxidants was absent in Nrf2-knockout mice, leading to the accumulation of LDH and exacerbation of cell death. This deterioration in both pancreatitis and injuries in distant organs intensified significantly. The results indicate that melatonin has an enhanced ability to protect against multiorgan damage caused by SAP, which is accomplished through the increase in Nrf2 expression. Additionally, Nrf2 initiates the activation of antioxidant genes that offer defense against cell death.


Subject(s)
Melatonin , NF-E2-Related Factor 2 , Oxidative Stress , Pancreatitis , Signal Transduction , Animals , NF-E2-Related Factor 2/metabolism , NF-E2-Related Factor 2/genetics , Melatonin/pharmacology , Melatonin/therapeutic use , Signal Transduction/drug effects , Pancreatitis/drug therapy , Pancreatitis/pathology , Pancreatitis/metabolism , Mice , Oxidative Stress/drug effects , Male , Antioxidants/pharmacology , Antioxidants/therapeutic use , Mice, Knockout , Pancreas/drug effects , Pancreas/pathology , Pancreas/metabolism , Mice, Inbred C57BL , Acute Disease
19.
Sci Rep ; 14(1): 11610, 2024 05 21.
Article in English | MEDLINE | ID: mdl-38773218

ABSTRACT

Although endoscopic necrosectomy (EN) is more frequently used to manage walled-off necrosis (WON), there is still debate over how much time should pass between the initial stent placement and the first necrosectomy. This study aims to determine the effect of performing EN within different timings after placing the initial stent on clinical outcomes for WON. A retrospective study on infected WON patients compared an early necrosectomy within one week after the initial stent placement with a necrosectomy that was postponed after a week. The primary outcomes compared the rate of clinical success and the need for additional intervention after EN to achieve WON resolution. 77 patients were divided into early and postponed necrosectomy groups. The complete resolution of WON within six months of follow-up was attained in 73.7% and 74.3% of patients in both the early and postponed groups. The early group tended to a greater need for additional intervention after EN (26.8% early necrosectomy vs. 8.3% postponed necrosectomy, P = 0.036). Our study does not demonstrate that early necrosectomy is superior to postponed necrosectomy in terms of clinical success rate, total count of necrosectomy procedures, procedure-related complications, length of hospitalization and prognosis. Conversely, patients in the postponed group received fewer additional interventions.


Subject(s)
Pancreatitis, Acute Necrotizing , Humans , Male , Female , Middle Aged , Retrospective Studies , Pancreatitis, Acute Necrotizing/surgery , Pancreatitis, Acute Necrotizing/pathology , Adult , Aged , Treatment Outcome , Endoscopy/methods , Stents/adverse effects , Necrosis , Drainage/methods
20.
J Am Chem Soc ; 146(20): 14349-14356, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38742424

ABSTRACT

High-purity CO2 rather than dilute CO2 (15 vol %, CO2/N2/O2 = 15:80:5, v/v/v) similar to the flue gas is currently used as the feedstock for the electroreduction of CO2, and the liquid products are usually mixed up with the cathode electrolyte, resulting in high product separation costs. In this work, we showed that a microporous conductive Bi-based metal-organic framework (Bi-HHTP, HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) can not only efficiently capture CO2 from the dilute CO2 under high humidity but also catalyze the electroreduction of the adsorbed CO2 into formic acid with a high current density of 80 mA cm-2 and a Faradaic efficiency of 90% at a very low cell voltage of 2.6 V. Importantly, the performance in a dilute CO2 atmosphere was close to that under a high-purity CO2 atmosphere. This is the first catalyst that can maintain exceptional eCO2RR performance in the presence of both O2 and N2. Moreover, by using dilute CO2 as the feedstock, a 1 cm-2 working electrode coating with Bi-HHTP can continuously produce a 200 mM formic acid aqueous solution with a relative purity of 100% for at least 30 h in a membrane electrode assembly (MEA) electrolyzer. The product does not contain electrolytes, and such a highly concentrated and pure formic acid aqueous solution can be directly used as an electrolyte for formic acid fuel cells. Comprehensive studies revealed that such a high performance might be ascribed to the CO2 capture ability of the micropores on Bi-HHTP and the lower Gibbs free energy of formation of the key intermediate *OCHO on the open Bi sites.

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