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1.
J Atheroscler Thromb ; 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39098034

ABSTRACT

AIMS: Pemafibrate substantially lowers serum triglyceride (TG) levels and increases high-density lipoprotein cholesterol (HDL-C) levels primarily in Japan, but it has not been evaluated in China. We aimed to confirm the efficacy and safety of pemafibrate in Chinese patients with hypertriglyceridemia and low HDL-C levels by comparing placebo and fenofibrate. METHODS: A multicenter, double-masked trial was conducted in China involving 344 patients with high TG and low HDL-C levels randomly assigned to one of four groups: pemafibrate 0.2 mg/d, pemafibrate 0.4 mg/d, fenofibrate 200 mg/d, or placebo for 12 weeks. The primary endpoint was the percentage change in fasting TG levels. RESULTS: The percentage change in TG levels from baseline was -34.1%, -44.0%, -30.5%, and 6.5% in the pemafibrate 0.2 mg/d, pemafibrate 0.4 mg/d, fenofibrate 200 mg/d, and placebo groups, respectively. Pemafibrate 0.4 mg/d significantly reduced TG levels compared with that in both placebo (p<0.0001) and fenofibrate groups (p=0.0083). Significant improvements in HDL-C, remnant cholesterol, and apolipoprotein A1 levels were also observed with both doses of pemafibrate than with the placebo. Pemafibrate showed significantly smaller changes in alanine aminotransferase, aspartate aminotransferase, and serum creatinine levels than those with fenofibrate. CONCLUSIONS: In Chinese patients, pemafibrate exhibited superior efficacy in improving TG levels and enhanced hepatic and renal safety compared to fenofibrate. Thus, pemafibrate may represent a promising therapeutic option for dyslipidemia in Chinese patients.

2.
Drug Des Devel Ther ; 18: 3399-3413, 2024.
Article in English | MEDLINE | ID: mdl-39100219

ABSTRACT

Background: Multidrug-resistant Gram-negative bacteria (MDR-GNB) are becoming increasingly common around the world, with carbapenems frequently serving as a last resort but being threatened by the growing incidence of carbapenemase-producing bacteria. Ceftazidime-avibactam (CAZ/AVI) is a potential agent against MDR-GNB but with limited clinical experience, particularly in critically ill immunosuppressed children. Methods: This study analyzed the use of CAZ/AVI as salvage treatment in severely infected immunosuppressed children from September 2019 to July 2022. Patients with confirmed GNB infection who received CAZ/AVI were matched with patients who received other antibiotics. Results: Twenty-five critically ill immunosuppressed children treated with CAZ/AVI were included. The majority had hematologic diseases. All patients presented with sepsis in all 30 courses. Septic shock presented in 36.7% of these courses. The primary sites of infection included bloodstream infection (20.0%), skin and skin structure infection (20.0%), intra-abdominal infection (13.3%) and hospital-acquired pneumonia (10.0%). Twelve of the 25 (48.0%) patients had positive microbiological cultures, mainly Pseudomonas aeruginosa and Klebsiella pneumoniae, including 5 carbapenem-resistant GNB-infected cases. Fifteen (50.0%) courses presented clinical improvement. For the initial course of each patient, the clinical response rate of the GNB recovered group was significantly higher than that of the group without GNB recovery (66.7% vs 23.1%, P = 0.047). The 14-day and 30-day mortality rates were 24.0% and 28.0%, respectively, which were significantly correlated with the absence of GNB recovery (P = 0.004 and 0.024, respectively) and hospital-acquired pneumonia as the primary site of infection (P = 0.001 and 0.006, respectively). There was no significant difference in major outcomes between patients who received CAZ/AVI and matched patients who received other antibiotics. Conclusion: CAZ/AVI could be considered a salvage strategy for immunosuppressed children with confirmed GNB infection. Caution should be taken when CAZ/AVI is applied to these patients in the absence of GNB recovery.


Subject(s)
Anti-Bacterial Agents , Azabicyclo Compounds , Ceftazidime , Drug Combinations , Salvage Therapy , Humans , Ceftazidime/administration & dosage , Ceftazidime/therapeutic use , Child , Male , Female , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/administration & dosage , Azabicyclo Compounds/administration & dosage , Azabicyclo Compounds/therapeutic use , Child, Preschool , Immunocompromised Host , Adolescent , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/microbiology , Drug Resistance, Multiple, Bacterial/drug effects , Retrospective Studies , Infant , Microbial Sensitivity Tests
3.
Nat Commun ; 15(1): 6674, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39107316

ABSTRACT

The driving force behind the Cenozoic India-Asia collision remains elusive. Using global-scale geodynamic modeling, we find that the continuous motion of the Indian plate is driven by a prominent upper-mantle flow pushing the thick Indian lithospheric root, originated from the northward rollover of the detached Neo-Tethyan slab and sinking slabs below East Asia. The maximum mantle drag occurs within the strong Indian lithosphere and is comparable in magnitude to that of slab pull (1013 N m-1). The thick cratonic root enhances both lithosphere-asthenosphere coupling and upper-plate compressional stress, thereby sustaining the topography of Tibetan Plateau. We show that the calculated resistant force from the India-Asia plate boundary is also close to that due to the gravitational potential energy of Tibetan Plateau. Here, we demonstrate that this mantle flow is key for the formation of the Tibetan Plateau and represents part of a hemispheric convergent flow pattern centered on central Asia.

4.
J Am Soc Nephrol ; 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39172518

ABSTRACT

BACKGROUND: IgA nephropathy is the most common primary glomerulonephritis worldwide, and there is emerging evidence linking galactose-deficient IgA1 (Gd-IgA1) to the pathogenesis of the disease. However, mouse models that can be used to study Gd-IgA1's origin of production, biochemical characteristics, and immune reactivity are lacking. METHODS: We generated a humanized IgA1 mouse model with transgenic expression of the human IGHA1 gene from the mouse chromosomal locus of IgA heavy chain. The IGHA1+/+ mice were crossed with complement factor H heterozygous mutant (FHW/R) to generate IGHA1+/+FHW/R mice. IGHA1+/+ mice were exposed to different levels of environmental pathogens in the first 4 months, as housed in either germ-free, specific pathogen-free, or conventional environments. In addition, wild-type C57BL/6J mice, IGHA1+/+ mice, and IGHA1+/+FHW/R mice were inoculated with Lactobacillus casei cell bacterial wall extract (LCWE) mixed with complete Freund's adjuvant (CFA) at two months of age to develop a mouse model of IgA nephropathy. RESULTS: Elevated levels of human IgA1 in blood circulation and mucosal sites were observed in IGHA1+/+ mice from exposure to pathogens. Compared to buffer-treated control mice, LCWE plus CFA-treated mice had moderately elevated levels of circulating human IgA1 (by one fold) and human IgA1 immune complexes (by two folds). Serum Gd-IgA1 levels increased fourfold following LCWE treatments. Analyses of the O-glycopeptides of the IgA1 hinge region confirmed hypo-galactosylation of IgA1, with the variety of the glycoforms matching those seen in clinical samples. Furthermore, LCWE induced persistent IgA1 and C3 deposition in the glomerular mesangial areas in association with mesangial expansion and hypercellularity, which are frequently observed in IgA nephropathy biopsies. The IGHA1+/+FHW/R mice stimulated with LCWE and CFA developed albuminuria and hematuria. CONCLUSIONS: We observed elevated plasma Gd-IgA1 levels with kidney deposition of IgA1 in the IGHA1+/+ mice following LCWE and CFA. In conjunction with factor H mutation, the mice exhibited severe glomerular alterations, associated with hematuria and albuminuria in resemblance of clinical IgA nephropathy.

5.
J Comput Aided Mol Des ; 38(1): 31, 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39177727

ABSTRACT

Human Hippo signaling pathway is an evolutionarily conserved regulator network that controls organ development and has been implicated in various cancers. Transcriptional enhanced associate domain-4 (TEAD4) is the final nuclear effector of Hippo pathway, which is activated by Yes-associated protein (YAP) through binding to two separated YAP regions of α1-helix and Ω-loop. Previous efforts have all been addressed on deriving peptide inhibitors from the YAP to target TEAD4. Instead, we herein attempted to rationally design a so-called 'YAP helixα1-trap' based on the TEAD4 to target YAP by using dynamics simulation and energetics analysis as well as experimental assays at molecular and cellular levels. The trap represents a native double-stranded helical hairpin covering a specific YAP-binding site on TEAD4 surface, which is expected to form a three-helix bundle with the α1-helical region of YAP, thus competitively disrupting TEAD4-YAP interaction. The hairpin was further stapled by a disulfide bridge across its two helical arms. Circular dichroism characterized that the stapling can effectively constrain the trap into a native-like structured conformation in free state, thus largely minimizing the entropy penalty upon its binding to YAP. Affinity assays revealed that the stapling can considerably improve the trap binding potency to YAP α1-helix by up to 8.5-fold at molecular level, which also exhibited a good tumor-suppressing effect at cellular level if fused with TAT cell permeation sequence. In this respect, it is considered that the YAP helixα1-trap-mediated blockade of Hippo pathway may be a new and promising therapeutic strategy against cancers.


Subject(s)
Adaptor Proteins, Signal Transducing , Antineoplastic Agents , DNA-Binding Proteins , Molecular Dynamics Simulation , Muscle Proteins , TEA Domain Transcription Factors , Transcription Factors , YAP-Signaling Proteins , Transcription Factors/chemistry , Transcription Factors/metabolism , Transcription Factors/antagonists & inhibitors , Humans , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Muscle Proteins/chemistry , Muscle Proteins/metabolism , Adaptor Proteins, Signal Transducing/chemistry , Adaptor Proteins, Signal Transducing/metabolism , Disulfides/chemistry , Disulfides/pharmacology , Protein Binding , Binding Sites , Cell Line, Tumor , Computer-Aided Design , Drug Design
6.
Sci Rep ; 14(1): 18242, 2024 08 06.
Article in English | MEDLINE | ID: mdl-39107474

ABSTRACT

Iron storage proteins, e.g., vertebrate ferritin, and the ferritin-like bacterioferritin (Bfr) and bacterial ferritin (Ftn), are spherical, hollow proteins that catalyze the oxidation of Fe2+ at binuclear iron ferroxidase centers (FOC) and store the Fe3+ in their interior, thus protecting cells from unwanted Fe3+/Fe2+ redox cycling and storing iron at concentrations far above the solubility of Fe3+. Vertebrate ferritins are heteropolymers of H and L subunits with only the H subunits having FOC. Bfr and Ftn were thought to coexist in bacteria as homopolymers, but recent evidence indicates these molecules are heteropolymers assembled from Bfr and Ftn subunits. Despite the heteropolymeric nature of vertebrate and bacterial ferritins, structures have been determined only for recombinant proteins constituted by a single subunit type. Herein we report the structure of Acinetobacter baumannii bacterioferritin, the first structural example of a heteropolymeric ferritin or ferritin-like molecule, assembled from completely overlapping Ftn homodimers harboring FOC and Bfr homodimers devoid of FOC but binding heme. The Ftn homodimers function by catalyzing the oxidation of Fe2+ to Fe3+, while the Bfr homodimers bind a cognate ferredoxin (Bfd) which reduces the stored Fe3+ by transferring electrons via the heme, enabling Fe2+ mobilization to the cytosol for incorporation in metabolism.


Subject(s)
Acinetobacter baumannii , Bacterial Proteins , Cytochrome b Group , Ferritins , Ferritins/chemistry , Ferritins/metabolism , Acinetobacter baumannii/metabolism , Cytochrome b Group/chemistry , Cytochrome b Group/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Crystallography, X-Ray , Models, Molecular , Protein Multimerization , Iron/metabolism , Iron/chemistry , Protein Subunits/chemistry , Protein Subunits/metabolism , Oxidation-Reduction , Protein Conformation
7.
Nat Commun ; 15(1): 6571, 2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39095372

ABSTRACT

Paleolatitudes of volcanic rocks reveal that prominent changes in volcanic trend of the Hawaii-Emperor hotspot chain represent meridional migration of the magma source. However, models assuming latitudinal plume migration fail to explain the observed age distribution, rock composition, and erratic paleolatitude changes of the oldest Emperor seamounts. Here we use data-assimilation models to better reproduce the Hawaii-Emperor hotspot track by systematically considering plate reconstruction, plume-lithosphere interaction, and simplified melt generation and migration. Our results show that plate drag and plume-ridge interaction are both important in explaining the observed seamount ages. These shallow dynamic processes could account for 50% of the observed paleolatitude's secular reduction and erratic variations over time, where the necessary southward migration of the Hawaiian plume root is significantly less than previously thought. We conclude that plume-lithosphere interaction represents a common mechanism in affecting hotspot track, and has important implications in understanding mantle dynamics and plate reference frames.

8.
Minerva Anestesiol ; 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39051884

ABSTRACT

Septic cardiomyopathy is a common complication in patients with sepsis, and is one of the indicators of poor prognosis. Its pathogenesis is complex, involving calcium ion imbalance in cardiomyocytes, nitric oxide (NO) synthesis disorder, mitochondrial abnormalities and immune inflammatory reaction, especially mitochondrial abnormalities. In this paper, the mechanism of mitochondrial abnormalities causing septic cardiomyopathy was discussed from the aspects of mitochondrial structure change, mitochondrial energy metabolism disorder, redox imbalance, mitochondrial calcium overload, mitochondrial biosynthesis and autophagy abnormalities.

9.
Curr Biol ; 34(15): 3429-3438.e4, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39047736

ABSTRACT

Rice paddy has been the main source of anthropogenic methane (CH4) emissions, with significant variations among rice varieties. 2-Acetyl-1-pyrroline (2-AP) is the key component of the pleasant aroma in fragrant rice. Here, we show that fragrant rice is metabolically active in nitrogen assimilation and exhibits high levels of 2-AP and that CH4 fluxes at the booting stage and cumulative emissions are 25.5% and 14.8% lower, respectively, in fragrant rice paddies compared with nonfragrant rice paddies. Three precursors involved in 2-AP synthesis-proline, glutamic acid, and ornithine-are identified as crucial nitrogen compounds that significantly promote CH4 oxidation in the rhizosphere. Augmenting 2-AP synthesis, either through foliar spraying or by utilizing CRISPR-Cas9 technology to generate knockout lines of BETAINE ALDEHYDE DEHYDROGENASE 2 gene, effectively enhances CH4 oxidation and reduces CH4 fluxes. Our findings reveal that the 2-AP metabolic pathway coordinates the carbon/nitrogen cycle to improve nitrogen assimilation along with high 2-AP levels and mitigate CH4 emissions in paddy ecosystems.


Subject(s)
Methane , Nitrogen , Oryza , Pyrroles , Oryza/metabolism , Oryza/genetics , Methane/metabolism , Nitrogen/metabolism , Pyrroles/metabolism
10.
J Hazard Mater ; 476: 135064, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-38968823

ABSTRACT

Intricate agricultural ecosystems markedly influence the dynamics of organic micropollutants, posing substantial threats to aquatic organisms and human health. This study examined the occurrence and distribution of organic micropollutants across soils, ditch sediment, and water within highly intensified farming setups. Using a non-targeted screening method, we identified 405 micropollutants across 10 sampling sites, which mainly included pesticides, pharmaceuticals, industrial chemicals, and personal care products. This inventory comprised emerging contaminants, banned pesticides, and controlled pharmaceuticals that had eluded detection via conventional monitoring. Targeted analysis showed concentrations of 3.99-1021 ng/g in soils, 4.67-2488 ng/g in sediment, and 12.5-9373 ng/L in water, respectively, for Σ40pesticides, Σ8pharmaceuticals, and Σ3industrial chemicals, indicating notable spatial variability. Soil organic carbon content and wastewater discharge were likely responsible for their spatial distribution. Principal component analysis and correlation analysis revealed a potential transfer of micropollutants across the three media. Particularly, a heightened correlation was decerned between soil and sediment micropollutant levels, highlighting the role of sorption processes. Risk quotients surpassed the threshold of 1 for 13-23 micropollutants across the three media, indicating high environmental risks. This study highlights the importance of employing non-targeted and targeted screening in assessing and managing environmental risks associated with micropollutants.


Subject(s)
Agriculture , Environmental Monitoring , Geologic Sediments , Soil Pollutants , Water Pollutants, Chemical , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Geologic Sediments/chemistry , Geologic Sediments/analysis , Soil Pollutants/analysis , Farms , Risk Assessment , Pesticides/analysis , Soil/chemistry
12.
New Phytol ; 243(5): 1776-1794, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38978318

ABSTRACT

Rare variants contribute significantly to the 'missing heritability' of quantitative traits. The genome-wide characteristics of rare variants and their roles in environmental adaptation of woody plants remain unexplored. Utilizing genome-wide rare variant association study (RVAS), expression quantitative trait loci (eQTL) mapping, genetic transformation, and molecular experiments, we explored the impact of rare variants on stomatal morphology and drought adaptation in Populus. Through comparative analysis of five world-wide Populus species, we observed the influence of mutational bias and adaptive selection on the distribution of rare variants. RVAS identified 75 candidate genes correlated with stomatal size (SS)/stomatal density (SD), and a rare haplotype in the promoter of serine/arginine-rich splicing factor PtoRSZ21 emerged as the foremost association signal governing SS. As a positive regulator of drought tolerance, PtoRSZ21 can recruit the core splicing factor PtoU1-70K to regulate alternative splicing (AS) of PtoATG2b (autophagy-related 2). The rare haplotype PtoRSZ21hap2 weakens binding affinity to PtoMYB61, consequently affecting PtoRSZ21 expression and SS, ultimately resulting in differential distribution of Populus accessions in arid and humid climates. This study enhances the understanding of regulatory mechanisms that underlie AS induced by rare variants and might provide targets for drought-tolerant varieties breeding in Populus.


Subject(s)
Adaptation, Physiological , Droughts , Gene Expression Regulation, Plant , Haplotypes , Plant Proteins , Plant Stomata , Populus , Populus/genetics , Populus/physiology , Populus/anatomy & histology , Plant Stomata/physiology , Plant Stomata/genetics , Haplotypes/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Adaptation, Physiological/genetics , Quantitative Trait Loci/genetics , Serine-Arginine Splicing Factors/genetics , Serine-Arginine Splicing Factors/metabolism , Genome-Wide Association Study , Alternative Splicing/genetics , Genetic Variation , Drought Resistance
13.
Acta Crystallogr F Struct Biol Commun ; 80(Pt 8): 173-182, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38990055

ABSTRACT

Klebsiella pneumoniae (Kp) is an infectious disease pathogen that poses a significant global health threat due to its potential to cause severe infections and its tendency to exhibit multidrug resistance. Understanding the enzymatic mechanisms of the oxygen-insensitive nitroreductases (Kp-NRs) from Kp is crucial for the development of effective nitrofuran drugs, such as nitrofurantoin, that can be activated as antibiotics. In this paper, three crystal structures of two Kp-NRs (PDB entries 7tmf/7tmg and 8dor) are presented, and an analysis of their crystal structures and their flavin mononucleotide (FMN)-binding mode is provided. The structures with PDB codes 7tmf (Kp-NR1a), 7tmg (Kp-NR1b) and 8dor (Kp-NR2) were determined at resolutions of 1.97, 1.90 and 1.35 Å, respectively. The Kp-NR1a and Kp-NR1b structures adopt an αß fold, in which four-stranded antiparallel ß-sheets are surrounded by five helices. With domain swapping, the ß-sheet was expanded with a ß-strand from the other molecule of the dimer. The difference between the structures lies in the loop spanning Leu173-Ala185: in Kp-NR1a the loop is disordered, whereas the loop adopts multiple conformations in Kp-NR1b. The FMN interactions within Kp-NR1/NR2 involve hydrogen-bond and π-stacking interactions. Kp-NR2 contains four-stranded antiparallel ß-sheets surrounded by eight helices with two short helices and one ß-sheet. Structural and sequence alignments show that Kp-NR1a/b and Kp-NR2 are homologs of the Escherichia coli oxygen-insensitive NRs YdjA and NfnB and of Enterobacter cloacae NR, respectively. By homology inference from E. coli, Kp-NR1a/b and Kp-NR2 may detoxify polynitroaromatic compounds and Kp-NR2 may activate nitrofuran drugs to cause bactericidal activity through a ping-pong bi-bi mechanism, respectively.


Subject(s)
Klebsiella pneumoniae , Models, Molecular , Nitroreductases , Klebsiella pneumoniae/enzymology , Crystallography, X-Ray , Nitroreductases/chemistry , Nitroreductases/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Amino Acid Sequence , Flavin Mononucleotide/metabolism , Flavin Mononucleotide/chemistry , Binding Sites , Protein Binding , Escherichia coli/metabolism , Escherichia coli/genetics , Escherichia coli/enzymology , Protein Conformation, beta-Strand , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Recombinant Proteins/genetics
14.
Plant Physiol Biochem ; 214: 108924, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38991593

ABSTRACT

LBD (LATERAL ORGAN BOUNDARIES DOMAIN) transcription factors are key regulators of plant growth and development. In this study, we functionally characterized the PagLBD4 gene in Populus (Populus alba × Populus glandulosa). Overexpression of PagLBD4 (PagLBD4OE) significantly repressed secondary xylem differentiation and secondary cell wall (SCW) deposition, while CRISPR/Cas9-mediated PagLBD4 knockout (PagLBD4KO) significantly increased secondary xylem differentiation and SCW deposition. Consistent with the functional analysis, gene expression analysis revealed that SCW biosynthesis pathways were significantly down-regulated in PagLBD4OE plants but up-regulated in PagLBD4KO plants. We also performed DNA affinity purification followed by sequencing (DAP-seq) to identify genes bound by PagLBD4. Integration of RNA sequencing (RNA-seq) and DAP-seq data identified 263 putative direct target genes (DTGs) of PagLBD4, including important regulatory genes for SCW biosynthesis, such as PagMYB103 and PagIRX12. Together, our results demonstrated that PagLBD4 is a repressor of secondary xylem differentiation and SCW biosynthesis in Populus, which possibly lead to the dramatic growth repression in PagLBD4OE plants.


Subject(s)
Cell Differentiation , Cell Wall , Gene Expression Regulation, Plant , Plant Proteins , Populus , Transcription Factors , Xylem , Populus/genetics , Populus/metabolism , Cell Wall/metabolism , Cell Wall/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Cell Differentiation/genetics , Xylem/metabolism , Xylem/genetics , Plants, Genetically Modified/metabolism
15.
J Med Chem ; 67(14): 11937-11956, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-38953866

ABSTRACT

Zoonotic coronaviruses are known to produce severe infections in humans and have been the cause of significant morbidity and mortality worldwide. SARS-CoV-2 was the largest and latest contributor of fatal cases, even though MERS-CoV has the highest case-fatality ratio among zoonotic coronaviruses. These infections pose a high risk to public health worldwide warranting efforts for the expeditious discovery of antivirals. Hence, we hereby describe a novel series of inhibitors of coronavirus 3CLpro embodying an N-substituted 2-pyrrolidone scaffold envisaged to exploit favorable interactions with the S3-S4 subsites and connected to an invariant Leu-Gln P2-P1 recognition element. Several inhibitors showed nanomolar antiviral activity in enzyme and cell-based assays, with no significant cytotoxicity. High-resolution crystal structures of inhibitors bound to the 3CLpro were determined to probe and identify the molecular determinants associated with binding, to inform the structure-guided optimization of the inhibitors, and to confirm the mechanism of action of the inhibitors.


Subject(s)
Antiviral Agents , Coronavirus 3C Proteases , Drug Design , SARS-CoV-2 , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/chemical synthesis , Humans , SARS-CoV-2/drug effects , Crystallography, X-Ray , Coronavirus 3C Proteases/antagonists & inhibitors , Coronavirus 3C Proteases/metabolism , Pyrrolidinones/pharmacology , Pyrrolidinones/chemistry , Structure-Activity Relationship , Animals , Models, Molecular
17.
Nat Commun ; 15(1): 5940, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39009563

ABSTRACT

Eunicellane diterpenoids, containing a typical 6,10-bicycle, are bioactive compounds widely present in marine corals, but rarely found in bacteria and plants. The intrinsic macrocycle exhibits innate structural flexibility resulting in dynamic conformational changes. However, the mechanisms controlling flexibility remain unknown. The discovery of a terpene synthase, MicA, that is responsible for the biosynthesis of a nearly non-flexible eunicellane skeleton, enable us to propose a feasible theory about the flexibility in eunicellane structures. Parallel studies of all eunicellane synthases in nature discovered to date, including 2Z-geranylgeranyl diphosphate incubations and density functional theory-based Boltzmann population computations, reveale that a trans-fused bicycle with a 2Z-configuration alkene restricts conformational flexibility resulting in a nearly non-flexible eunicellane skeleton. The catalytic route and the enzymatic mechanism of MicA are also elucidated by labeling experiments, density functional theory calculations, structural analysis of the artificial intelligence-based MicA model, and mutational studies.


Subject(s)
Alkyl and Aryl Transferases , Diterpenes , Alkyl and Aryl Transferases/metabolism , Alkyl and Aryl Transferases/genetics , Alkyl and Aryl Transferases/chemistry , Diterpenes/metabolism , Diterpenes/chemistry , Polyisoprenyl Phosphates/metabolism , Polyisoprenyl Phosphates/chemistry , Models, Molecular
18.
Plants (Basel) ; 13(13)2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38999588

ABSTRACT

BACKGROUND: DNA methylation can change rapidly to regulate the expression of stress-responsive genes. Previous studies have shown that there are significant differences in the cold resistance of winter rapeseed (Brassica rapa L.) after being domesticated in different selection environments; however, little is known about the epigenetic regulatory mechanisms of its cold resistance formation. METHODS: Four winter rapeseed materials ('CT-2360', 'MXW-1', '2018-FJT', and 'DT-7') domesticated in different environments were selected to analyze the DNA methylation level and pattern changes under low temperature using methylation-sensitive amplified polymorphism technology with 60 primer pairs. RESULTS: A total of 18 pairs of primers with good polymorphism were screened, and 1426 clear bands were amplified, with 594 methylation sites, accounting for 41.65% of the total amplified bands. The total methylation ratios of the four materials were reduced after low-temperature treatment, in which the DNA methylation level of 'CT-2360' was higher than that of the other three materials; the analysis of methylation patterns revealed that the degree of demethylation was higher than that of methylation in 'MXW-1', '2018-FJT', and 'DT-7', which were 22.99%, 19.77%, and 24.35%, respectively, and that the methylation events in 'CT-2360' were predominantly dominant at 22.95%. Fifty-three polymorphic methylated DNA fragments were randomly selected and further analyzed, and twenty-nine of the cloned fragments were homologous to genes with known functions. The candidate genes VQ22 and LOC103871127 verified the existence of different expressive patterns before and after low-temperature treatment. CONCLUSIONS: Our work implies the critical role of DNA methylation in the formation of cold resistance in winter rapeseed. These results provide a comprehensive insight into the adaptation epigenetic regulatory mechanism of Brassica rapa L. to low temperature, and the identified differentially methylated genes can also be used as important genetic resources for the multilateral breeding of winter-resistant varieties.

19.
BMC Nephrol ; 25(1): 213, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38956556

ABSTRACT

BACKGROUND: Certain occupations may predispose individuals to urolithiasis, a multi-factorial disease. The study aimed to evaluate the prevalence and related factors of nephrolithiasis in medical staff in Qingdao, China. METHODS: Physical examination results of 5115 in-service medical staff aged 22-60 years old were retrospectively analyzed. Multivariable logistic regression analysis and stratified analyses by age and gender were applied to explore the related factors of nephrolithiasis in these medical staff. RESULTS: The overall nephrolithiasis prevalence in medical staff in Qingdao, China was 4.65%. Doctors were more prone to nephrolithiasis than nurses (5.63% vs. 3.96%, P = 0.013) and the peak prevalence (6.69%) was observed in medical staff working in the emergency department (ED). Male gender (OR = 1.615, 95% CI = 1.123-2.323, P = 0.010), overweight or obesity (OR = 1.674, 95% CI = 1.266-2.214, P < 0.001), work seniority ≥ 10 years (OR = 2.489, 95%CI = 1.675-3.699, P < 0.001) and working in the ED (OR = 1.815, 95% CI = 1.202-2.742, P = 0.005) were independent predictors for nephrolithiasis in medical staff based on the results of multivariate logistic regression analysis. The associations between overweight or obesity and nephrolithiasis risk as well as between work seniority ≥ 10 years and nephrolithiasis risk in medical staff were independent of age or gender in stratified analysis. CONCLUSIONS: Nephrolithiasis prevalence in medical staff in Qingdao, China seemed not to be higher than that in the general population. Medical staff with work seniority ≥ 10 years and working in the ED should pay abundant attention to take measures to modify their nephrolithiasis risk.


Subject(s)
Nephrolithiasis , Humans , Male , Adult , Female , China/epidemiology , Nephrolithiasis/epidemiology , Retrospective Studies , Prevalence , Middle Aged , Cross-Sectional Studies , Young Adult , Risk Factors , Occupational Diseases/epidemiology , Medical Staff/statistics & numerical data
20.
Clin Kidney J ; 17(7): sfae157, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38979107

ABSTRACT

Background: Previous research indicates that coronavirus disease 2019 (COVID-19) infection may have a role in triggering immunoglobulin A (IgA) nephropathy. However, limited research has explored the clinical implications of COVID-19 infection in individuals already diagnosed with IgA nephropathy. This study aimed to determine whether COVID-19 infection independently affects the subsequent trajectory of kidney function in IgA nephropathy patients. Methods: This was a single-center cohort study. The study included 199 patients diagnosed with IgA nephropathy. The COVID-19 infection status was determined using a combined method: a questionnaire and the Health Code application, both administered at the end of 2022 in northern China. Kidney function trajectory was assessed by the estimated glomerular filtration rate (eGFR), calculated based on serum creatinine levels measured during follow-up outpatient visits. The primary endpoint of interest was the eGFR trajectory. Results: Out of the 199 participants, 75% (n = 181) reported a confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, determined through antigen or polymerase chain reaction tests, accounting for 79% (n = 143) of the infected patients. A significant majority (98%) experienced mild to moderate symptoms. Over a median follow-up period of 10.7 months post-COVID-19 infection, notable clinical events included gross hematuria in 30 patients (16.6%), which normalized within an average of 3 days. Additionally, a 2-fold increase in proteinuria or progression to the nephrotic range was observed in 10 individuals (5.5%). No cases of acute kidney injury were noted. COVID-19 exposure was associated with an absolute change in eGFR of 2.98 mL/min/1.73 m2 per month (95% confidence interval 0.46 to 5.50). However, in a fully adjusted model, the estimated changes in eGFR slope post-COVID-19 were -0.39 mL/min/1.73 m2 per month (95% confidence interval -0.83 to 0.06, P = .088) which included the possibility of no significant effect. Notably, a higher rate of kidney function decline was primarily observed in patients with a baseline eGFR <45 mL/min/1.73 m2 [-0.56 mL/min/1.73 m2 (-1.11 to -0.01), P = .048]. In the cohort, there were few instances of severe COVID-19 cases. The absence of long-term follow-up outcomes was observed. Conclusions: Overall, mild to moderate COVID-19 infection does not appear to significantly exacerbate the subsequent decline in kidney function among IgA nephropathy patients, particularly in those with preserved baseline kidney function.

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