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1.
Environ Sci Technol ; 58(23): 10388-10397, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38828512

ABSTRACT

Selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3-SCR) is an efficient NOx reduction strategy, while the denitrification (deNOx) catalysts suffer from serious deactivation due to the coexistence of multiple poisoning substances, such as alkali metal (e.g., K), SO2, etc., in industrial flue gases. It is essential to understand the interaction among various poisons and their effects on the deNOx process. Herein, the ZSM-5 zeolite-confined MnSmOx mixed (MnSmOx@ZSM-5) catalyst exhibited better deNOx performance after the poisoning of K, SO2, and/or K&SO2 than the MnSmOx and MnSmOx/ZSM-5 catalysts, the deNOx activity of which at high temperature (H-T) increased significantly (>90% NOx conversion in the range of 220-480 °C). It has been demonstrated that K would occupy both redox and acidic sites, which severely reduced the reactivity of MnSmOx/ZSM-5 catalysts. The most important, K element is preferentially deposited at -OH on the surface of ZSM-5 carrier due to the electrostatic attraction (-O-K). As for the K&SO2 poisoning catalyst, SO2 preferred to be combined with the surface-deposited K (-O-K-SO2ads) according to XPS and density functional theory (DFT) results, the poisoned active sites by K would be released. The K migration behavior was induced by SO2 over K-poisoned MnSmOx@ZSM-5 catalysts, and the balance of surface redox and acidic site was regulated, like a synergistic promoter, which led to K-poisoning buffering and activity recovery. This work contributes to the understanding of the self-detoxification interaction between alkali metals (e.g., K) and SO2 on deNOx catalysts and provides a novel strategy for the adaptive use of one poisoning substance to counter another for practical NOx reduction.


Subject(s)
Zeolites , Zeolites/chemistry , Catalysis , Oxidation-Reduction , Nitrogen Oxides/chemistry , Oxides/chemistry , Ammonia/chemistry , Denitrification , Metals/chemistry
2.
Environ Res ; 258: 119284, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38823618

ABSTRACT

High concentrations of PM2.5 with enriched levels of metallic constituents could significantly affect the health and comfort of metro employees. To avoid overestimating the exposure risks, we investigated the bioaccessibility of toxic metals (TMs) bound in PM2.5 from the Nanchang metro using Gamble's solution method, and qualitatively analyzed the impact of valence state and various sources on the bioaccessibility of TMs bound to PM2.5. The results showed that the bioaccessibility of the studied TMs ranged from 2.1% to 88.1%, with As, Ba, Co and Pb being the most bioaccessible and V, Fe and Cr being the less bioaccessible. The bioaccessibility of TMs in our subway PM2.5 samples varied based on their valence and species, showing higher valence states associated with increased bioaccessibility. Vehicle traffic, secondary aerosols and wheel/rail sources were found to be significantly and positively associated with the bioaccessibility of several TMs, implying a severe potential risk from these three sources. Although both non-carcinogenic and carcinogenic risks associated with total TMs were found to be high, only As and Cr(VI) posed a considerable carcinogenic risk to metro workers based on the bioaccessible fractions and were therefore priority pollutants. In addition, potential carcinogenic risk was found to be more severe in platform than that in ticket counter. The results indicate that considerable efforts are required to control and manage PM2.5 and the associated TMs in the Nanchang subway, particularly from traffic, wheel/rail and secondary sources, to protect the health of metro staff and the public.

3.
J Med Chem ; 67(11): 8730-8756, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38817193

ABSTRACT

The secretory glutaminyl cyclase (sQC) and Golgi-resident glutaminyl cyclase (gQC) are responsible for N-terminal protein pyroglutamation and associated with various human diseases. Although several sQC/gQC inhibitors have been reported, only one inhibitor, PQ912, is currently undergoing clinic trials for the treatment of Alzheimer's disease. We report an X-ray crystal structure of sQC complexed with PQ912, revealing that the benzimidazole makes "anchor" interactions with the active site zinc ion and catalytic triad. Structure-guided design and optimization led to a series of new benzimidazole derivatives exhibiting nanomolar inhibition for both sQC and gQC. In a MPTP-induced Parkinson's disease (PD) mouse model, BI-43 manifested efficacy in mitigating locomotor deficits through reversing dopaminergic neuronal loss, reducing microglia, and decreasing levels of the sQC/gQC substrates, α-synuclein, and CCL2. This study not only offers structural basis and new leads for drug discovery targeting sQC/gQC but also provides evidence supporting sQC/gQC as potential targets for PD treatment.


Subject(s)
Aminoacyltransferases , Benzimidazoles , Enzyme Inhibitors , Animals , Aminoacyltransferases/antagonists & inhibitors , Aminoacyltransferases/metabolism , Benzimidazoles/chemistry , Benzimidazoles/pharmacology , Benzimidazoles/chemical synthesis , Crystallography, X-Ray , Mice , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/therapeutic use , Structure-Activity Relationship , Disease Models, Animal , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Humans , Mice, Inbred C57BL , Drug Discovery , Male , Models, Molecular
5.
BMC Med ; 22(1): 96, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38443977

ABSTRACT

BACKGROUND: There is a lack of effective therapeutic strategies for amyotrophic lateral sclerosis (ALS); therefore, drug repurposing might provide a rapid approach to meet the urgent need for treatment. METHODS: To identify therapeutic targets associated with ALS, we conducted Mendelian randomization (MR) analysis and colocalization analysis using cis-eQTL of druggable gene and ALS GWAS data collections to determine annotated druggable gene targets that exhibited significant associations with ALS. By subsequent repurposing drug discovery coupled with inclusion criteria selection, we identified several drug candidates corresponding to their druggable gene targets that have been genetically validated. The pharmacological assays were then conducted to further assess the efficacy of genetics-supported repurposed drugs for potential ALS therapy in various cellular models. RESULTS: Through MR analysis, we identified potential ALS druggable genes in the blood, including TBK1 [OR 1.30, 95%CI (1.19, 1.42)], TNFSF12 [OR 1.36, 95%CI (1.19, 1.56)], GPX3 [OR 1.28, 95%CI (1.15, 1.43)], TNFSF13 [OR 0.45, 95%CI (0.32, 0.64)], and CD68 [OR 0.38, 95%CI (0.24, 0.58)]. Additionally, we identified potential ALS druggable genes in the brain, including RESP18 [OR 1.11, 95%CI (1.07, 1.16)], GPX3 [OR 0.57, 95%CI (0.48, 0.68)], GDF9 [OR 0.77, 95%CI (0.67, 0.88)], and PTPRN [OR 0.17, 95%CI (0.08, 0.34)]. Among them, TBK1, TNFSF12, RESP18, and GPX3 were confirmed in further colocalization analysis. We identified five drugs with repurposing opportunities targeting TBK1, TNFSF12, and GPX3, namely fostamatinib (R788), amlexanox (AMX), BIIB-023, RG-7212, and glutathione as potential repurposing drugs. R788 and AMX were prioritized due to their genetic supports, safety profiles, and cost-effectiveness evaluation. Further pharmacological analysis revealed that R788 and AMX mitigated neuroinflammation in ALS cell models characterized by overly active cGAS/STING signaling that was induced by MSA-2 or ALS-related toxic proteins (TDP-43 and SOD1), through the inhibition of TBK1 phosphorylation. CONCLUSIONS: Our MR analyses provided genetic evidence supporting TBK1, TNFSF12, RESP18, and GPX3 as druggable genes for ALS treatment. Among the drug candidates targeting the above genes with repurposing opportunities, FDA-approved drug-R788 and AMX served as effective TBK1 inhibitors. The subsequent pharmacological studies validated the potential of R788 and AMX for treating specific ALS subtypes through the inhibition of TBK1 phosphorylation.


Subject(s)
Aminopyridines , Amyotrophic Lateral Sclerosis , Humans , Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/genetics , Drug Repositioning , Mendelian Randomization Analysis , Protein Serine-Threonine Kinases/genetics
6.
Bioorg Chem ; 142: 106970, 2024 01.
Article in English | MEDLINE | ID: mdl-37984101

ABSTRACT

Targeting the epidermal growth factor receptor (EGFR) has been recognized as an effective strategy for treating non-small-cell lung cancer (NSCLC). Although several representative EGFR inhibitors have been approved for clinical use, it is highly desirable to develop highly potent and selective EGFR inhibitors with novel scaffolds because of the occurrence of acquired resistance after treatment. Here we first demonstrate that the 4-indolyl quinazoline derivatives could potently inhibit EGFR in vitro and in vivo, of which YS-67 effectively and selectively inhibits EGFR[WT] (IC50 = 5.2 nM), EGFR[d746-750] (IC50 = 9.6 nM) and EGFR[L858R] (IC50 = 1.9 nM). The TREEspot™ kinase interaction map further reveals the binding selectivity toward 468 kinases. YS-67 not only potently suppresses p-EGFR and p-AKT, but also effectively inhibits proliferation of A549 (IC50 = 4.1 µM), PC-9 (IC50 = 0.5 µM) and A431 cells (IC50 = 2.1 µM). YS-67 treatment also causes colony formation inhibition, arrests cell cycle progression at G0/G1 phases and induces apoptosis. More importantly, YS-67 is well tolerated in A431 xenograft model after oral administration, showing effective tumor growth suppression and low toxicity. Collectively, YS-67 represents an underexplored scaffold for developing new EGFR inhibitors.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/metabolism , Quinazolines , Lung Neoplasms/drug therapy , Cell Proliferation , Protein Kinase Inhibitors , Cell Line, Tumor , ErbB Receptors , Mutation
7.
BMC Pediatr ; 23(1): 561, 2023 11 13.
Article in English | MEDLINE | ID: mdl-37957626

ABSTRACT

OBJECTIVE: Our present study utilized case-control research to explore the relationship between specific circRNAs and pediatric obesity through a literature review and bioinformatics and to predict their possible biological functions, providing ideas for epigenetic mechanism studies of pediatric obesity. METHODS: CircRNAs related to pediatric obesity were preliminarily screened by a literature review and qRT-PCR. CircRNA expression in children with obesity (n = 75) and control individuals (n = 75) was confirmed with qRT-PCR in a case-control study. This was followed by bioinformatics analyses, such as GO analysis, KEGG pathway analysis, and ceRNA network construction. Multivariate logistic regression was utilized to analyze the effects of circRNAs on obesity. A receiver operating characteristic (ROC) curve was also drawn to explore the clinical application value of circRNAs in pediatric obesity. RESULTS: Has_circ_0046367 and hsa_circ_0000284 were separately validated to be statistically downregulated and upregulated, respectively, in the peripheral blood mononuclear cells of children with obesity and revealed as independent indicators of increased CHD risk [hsa_circ_0046367 (OR = 0.681, 95% CI: 0.480 ~ 0.967) and hsa_circ_0000284 (OR = 1.218, 95% CI: 1.041 ~ 1.424)]. The area under the ROC curve in the combined analysis of hsa_circ_0046367 and hsa_circ_0000284 was 0.706 (95% CI: 0.623 ~ 0.789). Enrichment analyses revealed that these circRNAs were actively involved in neural plasticity mechanisms, cell secretion and signal regulation. CONCLUSION: The present research revealed that low expression of hsa_circ_0046367 and high expression of hsa_circ_0000284 are risk factors for pediatric obesity and that neural plasticity mechanisms are closely related to obesity.


Subject(s)
Pediatric Obesity , RNA, Circular , Child , Humans , RNA, Circular/genetics , Pediatric Obesity/genetics , Case-Control Studies , Leukocytes, Mononuclear , Computational Biology
8.
J Med Chem ; 66(19): 13746-13767, 2023 10 12.
Article in English | MEDLINE | ID: mdl-37791640

ABSTRACT

Metallo-ß-lactamases (MBLs) are zinc-dependent enzymes capable of hydrolyzing all bicyclic ß-lactam antibiotics, posing a great threat to public health. However, there are currently no clinically approved MBL inhibitors. Despite variations in their active sites, MBLs share a common catalytic mechanism with carbapenems, forming similar reaction species and hydrolysates. We here report the development of 2-aminothiazole-4-carboxylic acids (AtCs) as broad-spectrum MBL inhibitors by mimicking the anchor pharmacophore features of carbapenem hydrolysate binding. Several AtCs manifested potent activity against B1, B2, and B3 MBLs. Crystallographic analyses revealed a common binding mode of AtCs with B1, B2, and B3 MBLs, resembling binding observed in the MBL-carbapenem product complexes. AtCs restored Meropenem activity against MBL-producing isolates. In the murine sepsis model, AtCs exhibited favorable synergistic efficacy with Meropenem, along with acceptable pharmacokinetics and safety profiles. This work offers promising lead compounds and a structural basis for the development of potential drug candidates to combat MBL-mediated antimicrobial resistance.


Subject(s)
Carbapenems , beta-Lactamase Inhibitors , Animals , Mice , beta-Lactamase Inhibitors/pharmacology , beta-Lactamase Inhibitors/chemistry , Carbapenems/pharmacology , Meropenem/pharmacology , Carboxylic Acids , beta-Lactamases/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
9.
NPJ Parkinsons Dis ; 9(1): 146, 2023 Oct 21.
Article in English | MEDLINE | ID: mdl-37865667

ABSTRACT

Genome­wide association studies (GWASs) have revealed numerous loci associated with Parkinson's disease (PD). However, some potential causal/risk genes were still not revealed and no etiological therapies are available. To find potential causal genes and explore genetically supported drug targets for PD is urgent. By integrating the expression quantitative trait loci (eQTL) and protein quantitative trait loci (pQTL) datasets from multiple tissues (blood, cerebrospinal fluid (CSF) and brain) and PD GWAS summary statistics, a pipeline combing Mendelian randomization (MR), Steiger filtering analysis, Bayesian colocalization, fine mapping, Protein-protein network and enrichment analysis were applied to identify potential causal genes for PD. As a result, GPNMB displayed a robust causal role for PD at the protein level in the blood, CSF and brain, and transcriptional level in the brain, while the protective role of CD38 (in brain pQTL and eQTL) was also identified. We also found inconsistent roles of DGKQ on PD between protein and mRNA levels. Another 9 proteins (CTSB, ARSA, SEC23IP, CD84, ENTPD1, FCGR2B, BAG3, SNCA, FCGR2A) were associated with the risk for PD based on only a single pQTL after multiple corrections. We also identified some proteins' interactions with known PD causative genes and therapeutic targets. In conclusion, this study suggested GPNMB, CD38, and DGKQ may act in the pathogenesis of PD, but whether the other proteins involved in PD needs more evidence. These findings would help to uncover the genes underlying PD and prioritize targets for future therapeutic interventions.

10.
J Med Chem ; 66(16): 11517-11535, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37556731

ABSTRACT

Sepsis-associated acute kidney injury (AKI) is a serious clinical problem without effective drugs. Inhibition of sirtuin 5 (SIRT5) has been confirmed to protect against AKI, suggesting that SIRT5 inhibitors might be a promising therapeutic approach for AKI. Herein, structural optimization was performed on our previous compound 1 (IC50 = 3.0 µM), and a series of 2,4,5-trisubstituted pyrimidine derivatives have been synthesized. The structure-activity relationship (SAR) analysis led to the discovery of three nanomolar level SIRT5 inhibitors, of which the most potent compound 58 (IC50 = 310 nM) was demonstrated to be a substrate-competitive and selective inhibitor. Importantly, 58 significantly alleviated kidney dysfunction and pathological injury in both lipopolysaccharide (LPS)- and cecal ligation/perforation (CLP)-induced septic AKI mice. Further studies revealed that 58 regulated protein succinylation and the release of proinflammatory cytokines in the kidneys of septic AKI mice. Collectively, these results highlighted that targeting SIRT5 has a therapeutic potential against septic AKI.


Subject(s)
Acute Kidney Injury , Sepsis , Sirtuins , Animals , Mice , Acute Kidney Injury/drug therapy , Kidney , Pyrimidines/pharmacology , Pyrimidines/therapeutic use , Pyrimidines/metabolism , Sepsis/complications , Sepsis/drug therapy , Sirtuins/antagonists & inhibitors , Structure-Activity Relationship
11.
Eur J Med Chem ; 257: 115473, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37209449

ABSTRACT

The emergence of metallo-ß-lactamases (MBLs) confers resistance to nearly all the ß-lactam antibiotics, including carbapenems. Currently, there is a lack of clinically useful MBL inhibitors, making it crucial to discover new inhibitor chemotypes that can potently target multiple clinically relevant MBLs. Herein we report a strategy that utilizes a metal binding pharmacophore (MBP) click approach to identify new broad-spectrum MBL inhibitors. Our initial investigation identified several MBPs including phthalic acid, phenylboronic acid and benzyl phosphoric acid, which were subjected to structural transformations using azide-alkyne click reactions. Subsequent structure-activity relationship analyses led to the identification of several potent broad-spectrum MBL inhibitors, including 73 that manifested IC50 values ranging from 0.00012 µM to 0.64 µM against multiple MBLs. Co-crystallographic studies demonstrated the importance of MBPs in engaging with the MBL active site anchor pharmacophore features, and revealed the unusual two-molecule binding modes with IMP-1, highlighting the critical role of flexible active site loops in recognizing structurally diverse substrates/inhibitors. Our work provides new chemotypes for MBL inhibition and establishes a MBP click-derived paradigm for inhibitor discovery targeting MBLs as well as other metalloenzymes.


Subject(s)
Pharmacophore , beta-Lactamase Inhibitors , beta-Lactamase Inhibitors/pharmacology , beta-Lactamase Inhibitors/chemistry , beta-Lactamases/metabolism , Structure-Activity Relationship , Monobactams , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
12.
Front Endocrinol (Lausanne) ; 14: 1114250, 2023.
Article in English | MEDLINE | ID: mdl-37082119

ABSTRACT

Objective: This study evaluated whether paternal body mass index (BMI) before pregnancy was a risk factor for maternal-neonatal outcomes and long-term prognosis in offspring. Methods: This study included 29,518 participants from eight cities in Fujian, China using a stratified cluster random sampling method from May to September 2019. They were divided into four groups based on paternal BMI. Univariate and multivariate logistic regression were used to explore the relationship between paternal BMI groups, maternal-neonatal outcomes, and long-term prognosis in offspring. Further subgroup analysis was conducted to examine the stability of the risk. Results: The incidences of hypertensive disorder complicating pregnancy (HDCP), cesarean delivery, gestational weight gain (GWG) over guideline, and macrosomia were significantly higher in the paternal overweight and obesity group. Importantly, this study demonstrated that the incidence of asthma, hand-foot-and-mouth disease (HFMD), anemia, dental caries, and obesity of adolescents in paternal obesity increased. Furthermore, logistic regression and subgroup analysis confirm paternal obesity is a risk factor for HDCP, cesarean delivery, and macrosomia. It caused poor long-term prognosis in adolescents, including asthma, dental caries, and HFMD. Conclusions: Paternal obesity is a risk factor for adverse maternal-neonatal outcomes and poor long-term prognosis in adolescents. In addition to focusing on maternal weight, expectant fathers should pay more attention to weight management since BMI is a modifiable risk factor. Preventing paternal obesity can lead to better maternal and child outcomes. It would provide new opportunities for chronic diseases.


Subject(s)
Fathers , Obesity , Adolescent , Child , Female , Humans , Infant, Newborn , Male , Pregnancy , Dental Caries , Fetal Macrosomia/etiology , Obesity/complications , Obesity/diagnosis , Obesity/epidemiology , Prognosis , Weight Gain , Risk Factors , Body Mass Index , Pregnancy Complications/etiology , Pregnancy Outcome
13.
Chemosphere ; 329: 138613, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37030352

ABSTRACT

The synergistic degradation of VOCs and NOx that were emitted from the incineration of municipal and medical wastes by a single catalyst is challenging, due to the poor activity at low temperatures, and the SO2 poisoning on the active sites. Herein, N-doped TiO2 (N-TiO2) was used as the support for designing a highly efficient and stable catalyst system for CB/NOx synergistic degradation even in the presence of SO2. The prepared SbPdV/N-TiO2 catalyst, which presented excellent activity and tolerance to SO2 in the CBCO + SCR process, was investigated by a series of characterizations (such as XRD, TPD, XPS, H2-TPR and so on) as well as DFT calculations. The electronic structure of the catalyst was effectively modulated after N doping, resulting in effective charge flow between the catalyst surface and gas molecules. More importantly, the adsorption and deposition of sulfur species and reaction transient intermediates on active centers were restrained, while a new N adsorption center for NOx was provided. Abundant adsorption centers and superior redox properties ensured smooth CB/NOx synergistic degradation. The removal of CB mainly follows the L-H mechanism, while NOx elimination follows both E-R and L-H mechanisms. As a result, N doping provides a new approach to develop more advanced anti-SO2 poisoning CB/NOx synergistic catalytic removal systems for extensive applications.


Subject(s)
Ammonia , Oxides , Oxides/chemistry , Ammonia/chemistry , Titanium/chemistry , Oxidation-Reduction
14.
Trends Microbiol ; 31(7): 735-748, 2023 07.
Article in English | MEDLINE | ID: mdl-36858862

ABSTRACT

Resistance to ß-lactam antibiotics is rapidly growing, substantially due to the spread of serine-ß-lactamases (SBLs) and metallo-ß-lactamases (MBLs), which efficiently catalyse ß-lactam hydrolysis. Combinations of a ß-lactam antibiotic with an SBL inhibitor have been clinically successful; however, no MBL inhibitors have been developed for clinical use. MBLs are a worrying resistance vector because they catalyse hydrolysis of all ß-lactam antibiotic classes, except the monobactams, and they are being disseminated across many bacterial species worldwide. Here we review the classification, structures, substrate profiles, and inhibition mechanisms of MBLs, highlighting current clinical problems due to MBL-mediated resistance and progress in understanding and combating MBL-mediated resistance.


Subject(s)
Anti-Bacterial Agents , beta-Lactamase Inhibitors , Anti-Bacterial Agents/pharmacology , beta-Lactamase Inhibitors/pharmacology , beta-Lactamase Inhibitors/chemistry , Drug Resistance, Bacterial , beta-Lactamases/chemistry , beta-Lactams/pharmacology
15.
Bioorg Chem ; 135: 106487, 2023 06.
Article in English | MEDLINE | ID: mdl-36996510

ABSTRACT

SIRT5 has been implicated in various physiological processes and human diseases, including cancer. Development of new highly potent, selective SIRT5 inhibitors is still needed to investigate disease-related mechanisms and therapeutic potentials. We here report new ε-N-thioglutaryllysine derivatives, which were designed according to SIRT5-catalysed deacylation reactions. These ε-N-thioglutaryllysine derivatives displayed potent SIRT5 inhibition, of which the potential photo-crosslinking derivative 8 manifested most potent inhibition with an IC50 value of 120 nM to SIRT5, and low inhibition to SIRT1-3 and SIRT6. The enzyme kinetic assays revealed that the ε-N-thioglutaryllysine derivatives inhibit SIRT5 by lysine-substrate competitive manner. Co-crystallographic analyses demonstrated that 8 binds to occupy the lysine-substate binding site by making hydrogen-bonding and electrostatic interactions with SIRT5-specific residues, and is likely positioned to react with NAD+ and form stable thio-intermediates. Compound 8 was observed to have low photo-crosslinking probability to SIRT5, possibly due to inappropriate position of the diazirine group as observed in SIRT5:8 crystal structure. This study provides useful information for developing drug-like inhibitors and cross-linking chemical probes for SIRT5-related studies.


Subject(s)
Sirtuins , Humans , Sirtuins/metabolism , Lysine/chemistry , Binding Sites
16.
J Antimicrob Chemother ; 78(5): 1288-1294, 2023 05 03.
Article in English | MEDLINE | ID: mdl-36995982

ABSTRACT

BACKGROUND: We found a carbapenem-resistant Escherichia coli without known carbapenemase-encoding genes and performed a study to identify the possible new carbapenemase. METHODS: The production of carbapenemase was examined using the modified carbapenem inactivation method. The strain was subjected to short- and long-read genome sequencing and the complete genome was obtained by hybrid assembly. The gene encoding a potential new OXA-type carbapenemase was cloned. The enzyme was purified and was then subjected to kinetic assays. Molecular docking analysis of the enzyme was performed using the MOE software suite. Mating experiments were attempted to obtain the plasmid carrying the corresponding gene. RESULTS: We identified and characterized a novel class D carbapenem-hydrolysing ß-lactamase, OXA-1041, in a carbapenem-resistant E. coli clinical strain. OXA-1041 had 89.77% (237/264) amino acid identity with OXA-427, a known carbapenemase. By cloning in an E. coli laboratory strain, blaOXA-1041 was found to reduce susceptibility to ertapenem by 16 times (MIC 0.25 versus 0.016 mg/L) and meropenem by four times (MIC 0.06 versus 0.016 mg/L) but did not significantly reduce susceptibility to imipenem and doripenem. Enzyme kinetic measurement of purified OXA-1041 showed that OXA-1041 could hydrolyse ertapenem and meropenem with a turnover number (kcat)/Michaelis constant (KM) of 8.57 and 3.63 mM-1s-1, respectively. The complete genome contained a single plasmid (223 341 bp, IncF, containing five replicons), which was self-transmissible. blaOXA-1041 was downstream of insertion sequence ISCR1 and there were three tandem copies of ISCR1-blaOXA-1041-creDΔ (encoding an envelope protein) on this plasmid. CONCLUSIONS: The above findings suggest OXA-1041 is a new plasmid-encoded carbapenemase with preferential activity against ertapenem.


Subject(s)
Carbapenems , Escherichia coli , Carbapenems/pharmacology , Carbapenems/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Meropenem , Ertapenem/pharmacology , Molecular Docking Simulation , beta-Lactamases/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Microbial Sensitivity Tests
17.
J Org Chem ; 88(6): 3802-3807, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36822154

ABSTRACT

The organocatalytic asymmetric Morita-Baylis-Hillman (MBH) reaction of isatin derivatives with various vinyl sulfones is disclosed. Chiral sulfone-containing 3-hydroxyoxindoles were produced in good to high yields and with good to high ee's. This report displays an unprecedented example to apply activated alkenes with sulfone moiety other than carbonyl groups in asymmetric MBH reactions and provides an efficient strategy to incorporate the sulfone functional group for the synthesis of chiral 3-hydroxyoxindoles.

18.
J Med Chem ; 66(1): 1063-1081, 2023 01 12.
Article in English | MEDLINE | ID: mdl-36580346

ABSTRACT

Interrupting the embryonic ectoderm development (EED)-H3K27me3 interaction represents a promising strategy to allosterically inhibit polycomb repressive complex 2 (PRC2) for cancer therapy. In this work, we report the structure-based design of new triazolopyrimidine-based EED inhibitors, which structurally feature the electron-rich indole ring at the C8 position. Particularly, ZJH-16 directly binds to EED (HTRF IC50 = 2.72 nM, BLI KD = 4.4 nM) and potently inhibits the growth of KARPAS422 and Pfeiffer cells. In both cells, ZJH-16 is selectively engaged with EED and reduces H3K27 trimethylation levels. ZJH-16 inhibits the gene silencing function of PRC2 in KARPAS422 cells. ZJH-16 possesses favorable pharmacokinetic (PK) profiles with an excellent oral bioavailability (F = 94.7%). More importantly, ZJH-16 shows robust tumor regression in the KARPAS422 xenograft model after oral administration with the tumor growth inhibition reaching nearly 100%. The robust antitumor efficacy and favorable PK profiles of ZJH-16 warrant further advanced preclinical development for lymphoma treatment.


Subject(s)
Histones , Lymphoma , Humans , Histones/metabolism , Polycomb Repressive Complex 2/metabolism
19.
Nucleic Acids Res ; 51(D1): D593-D602, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36243971

ABSTRACT

Metalloenzymes are attractive research targets in fields of chemistry, biology, and medicine. Given that metalloenzymes can manifest conservation of metal-coordination and ligand binding modes, the excavation and expansion of metalloenzyme-specific knowledge is of interest in bridging metalloenzyme-related fields. Building on our previous metalloenzyme-ligand association database, MeLAD, we have expanded the scope of metalloenzyme-specific knowledge and services, by forming a versatile platform, termed the Metalloenzyme Data Bank and Analysis (MeDBA). The MeDBA provides: (i) manual curation of metalloenzymes into different categories, that this M-I, M-II and M-III; (ii) comprehensive information on metalloenzyme activities, expression profiles, family and disease links; (iii) structural information on metalloenzymes, in particular metal binding modes; (iv) metalloenzyme substrates and bioactive molecules acting on metalloenzymes; (v) excavated metal-binding pharmacophores and (vi) analysis tools for structure/metal active site comparison and metalloenzyme profiling. The MeDBA is freely available at https://medba.ddtmlab.org.


Subject(s)
Databases, Protein , Metalloproteins , Catalytic Domain , Ligands , Metalloproteins/metabolism , Metals , Enzymes
20.
Article in English | MEDLINE | ID: mdl-36294276

ABSTRACT

The COVID-19 pandemic may constitute an "obesogenic lifestyle" that results in exacerbating childhood obesity. However, studies investigating regional sociodemographic factors including different age groups or sexes in children with obesity are lacking. We aimed to clarify the high obesity prevalence populations of preschool children to provide a regional basis for children's health policy during the COVID-19 school closures. From May to September 2019, a total of 29,518 preschool children were included in a large sample, multicenter cross-sectional study to explore physical status in Fujian Province by stratified cluster random sampling. In October 2019 and October 2020, we also conducted a cross-sectional study exploring physical development including changes in height, weight, and BMI of 1688 preschool children in Fuzhou before and after the COVID-19 school closures. Student' s t-test, Mann-Whitney U test, or chi-square test was used to assess differences in physical development and overweight and obesity rates among preschool children before and after school closures. For regional factors, the weight of urban preschool children of all ages became higher after the outbreak (p (age 3-4) = 0.009; p (age 4-5) < 0.001; p (age 5-6) = 0.002). For sex factors, overweight and obesity in boys had a greater prevalence than in girls before and after the outbreak. In four age groups, overweight and obesity rates in the 5-year-old group (15.5% and 9.9%) were higher than before (11.4% and 6.0%). The weight and BMI of 4- to 5-year-old children also increased faster than before (p < 0.001). The COVID-19 pandemic has promoted the epidemic of childhood obesity. Living in urban/coastal (economically developed) areas, boys, and aged 4-6 years old may be a susceptible population to obesity development after the outbreak.


Subject(s)
COVID-19 , Pediatric Obesity , Child , Male , Female , Humans , Child, Preschool , Overweight/epidemiology , Pediatric Obesity/epidemiology , COVID-19/epidemiology , Cross-Sectional Studies , Pandemics , China/epidemiology , Schools , Prevalence , Body Mass Index
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