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1.
Aging (Albany NY) ; 16(11): 9625-9648, 2024 May 31.
Article En | MEDLINE | ID: mdl-38829771

Currently, the repair of large bone defects still faces numerous challenges, with the most crucial being the lack of large bone grafts with good osteogenic properties. In this study, a novel bone repair implant (degradable porous zinc scaffold/BF Exo composite implant) was developed by utilizing laser melting rapid prototyping 3D printing technology to fabricate a porous zinc scaffold, combining it under vacuum conditions with highly bioactive serum exosomes (BF EXO) and Poloxamer 407 thermosensitive hydrogel. The electron microscope revealed the presence of tea saucer-shaped exosomes with a double-layered membrane structure, ranging in diameter from 30-150 nm, with an average size of 86.3 nm and a concentration of 3.28E+09 particles/mL. In vitro experiments demonstrated that the zinc scaffold displayed no significant cytotoxicity, and loading exosomes enhanced the zinc scaffold's ability to promote osteogenic cell activity while inhibiting osteoclast activity. In vivo experiments on rabbits indicated that the hepatic and renal toxicity of the zinc scaffold decreased over time, and the loading of exosomes alleviated the hepatic and renal toxic effects of the zinc scaffold. Throughout various stages of repairing radial bone defects in rabbits, loading exosomes reinforced the zinc scaffold's capacity to enhance osteogenic cell activity, suppress osteoclast activity, and promote angiogenesis. This effect may be attributed to BF Exo's regulation of p38/STAT1 signaling. This study signifies that the combined treatment of degradable porous zinc scaffolds and BF Exo is an effective and biocompatible strategy for bone defect repair therapy.


Bone Regeneration , Exosomes , Osteogenesis , Printing, Three-Dimensional , Radius , Tissue Scaffolds , Zinc , Animals , Exosomes/metabolism , Exosomes/transplantation , Rabbits , Radius/surgery , Osteogenesis/drug effects , Porosity , Bone Regeneration/drug effects , Male
2.
Environ Res ; 257: 119291, 2024 May 30.
Article En | MEDLINE | ID: mdl-38823607

The presence of butylparaben (BP), a prevalent pharmaceutical and personal care product, in surface waters has raised concerns regarding its impact on aquatic ecosystems. Despite its frequent detection, the toxicity of BP to the cyanobacterium Microcystis aeruginosa remains poorly understood. This study investigates the influence of BP on the growth and physiological responses of M. aeruginosa. Results indicate that low concentrations of BP (below 2.5 mg/L) have negligible effects on M. aeruginosa growth, whereas higher concentrations (5 mg/L and 10 mg/L) lead to significant growth inhibition. This inhibition is attributed to the severe disruption of photosynthesis, evidenced by decreased Fv/Fm values and chlorophyll a content. BP exposure also triggers the production of reactive oxygen species (ROS), resulting in elevated activity of antioxidant enzymes. Excessive ROS generation stimulates the production of microcystin-LR (MC-LR). Furthermore, lipid peroxidation and cell membrane damage indicate that high BP concentrations cause cell membrane rupture, facilitating the release of MC-LR into the environment. Transcriptome analysis reveals that BP disrupts energy metabolic processes, particularly affecting genes associated with photosynthesis, carbon fixation, electron transport, glycolysis, and the tricarboxylic acid cycle. These findings underscore the profound physiological impact of BP on M. aeruginosa and highlight its role in stimulating the production and release of MC-LR, thereby amplifying environmental risks in aquatic systems.

3.
Clin Chim Acta ; 560: 119751, 2024 Jun 15.
Article En | MEDLINE | ID: mdl-38830523

BACKGROUND: The metabolic or proliferative abnormalities that are characteristic of tumor cells can lead to abnormal fibrinolysis or coagulation system activity, with certain tumors exhibiting hypercoagulability or existing in a fibrinolytic state. However, the utility of biomarkers of coagulation and fibrinolysis when seeking to differentiate between benign gallbladder disease and malignant gallbladder tumors remains uncertain. METHODS: This study included a total of 81 patients with benign gallbladder polyps and 94 patients with malignant gallbladder tumors. Pre-biopsy or pretreatment levels of PT, APTT, FIB, D-dimer, FDP, PLT, PIC, TAT, TM, and t-PAIC from these patients were compared using Mann-Whitney tests. The baseline data of the patients were analyzed using chi-square tests, and the diagnostic utility of these biomarkers in distinguishing between benign and malignant gallbladder lesions was evaluated using ROC curves, and Spearman correlation analysis was employed to assess the correlation between these indicators and tumor parameters. RESULTS: The average age of malignant gallbladder tumor group was higher than benign gallbladder polyp group. And the base line analysis showed that there was a statistic difference in age, history of smoking, drinking, biliary tract disease, BMI of over weight between these two groups. In patients with malignant gallbladder tumors, FIB, D-dimer, FDP, PIC, TAT, TM, and t-PAIC levels were significantly elevated relative to those in patients affected by benign gallbladder polyp. The AUC for FIB, D-dimer, and FDP was 0.8469, 0.6514, 0.5950, while for PIC, TAT, TM, t-PAIC and four biomarker combined diagnosed was 0.8455, 0.6554, 0.7130, 0.6806, and 0.8859. Among these, TM was associated with the vascular invasion of tumor patients; TAT and t-PAIC were associated with neural invasion; D-dimer and FDP were related to the maximum tumor diameter; and FDP had a certain correlation with the tumor stage. CONCLUSIONS: In gallbladder tumor patients, conventional coagulation metrics like FIB, D-dimer, and FDP, as well as newer thrombotic indicators such as PIC, TAT, TM, and t-PAIC, were obviously increased. Correlations with tumor parameters suggested their potential as biomarkers to distinguish benign from malignant gallbladder growths.


Fibrinolysis , Gallbladder Neoplasms , Humans , Gallbladder Neoplasms/blood , Gallbladder Neoplasms/diagnosis , Gallbladder Neoplasms/pathology , Female , Male , Cross-Sectional Studies , Middle Aged , Aged , Blood Coagulation , Adult , Biomarkers, Tumor/blood , Diagnosis, Differential , Biomarkers/blood , Fibrin Fibrinogen Degradation Products/analysis , Fibrin Fibrinogen Degradation Products/metabolism
4.
Phys Chem Chem Phys ; 26(25): 17631-17644, 2024 Jun 26.
Article En | MEDLINE | ID: mdl-38864351

Reaction kinetics of hydrogen atom abstraction from six alkyl cyclohexanes, methyl cyclohexane (MCH), ethyl cyclohexane (ECH), n-propyl cyclohexane (nPCH), iso-propyl cyclohexane (iPCH), sec-butyl cyclohexane (sBCH) and iso-butyl cyclohexane (iBCH), by the H atom are systematically studied in this work. The M06-2X method combined with the 6-311++G(d,p) basis set is used to perform geometry optimization, frequency analysis and zero-point energy calculations for all species. The intrinsic reaction coordinate (IRC) calculations are performed to confirm the transition states connecting the reactants and products correctly. One-dimensional hindered rotors are used to treat the low frequency torsional models with potentials scanned at the M06-2X/6-31G level of theory. Electronic single-point energy calculations for all reactants, transition states, and products are performed at the QCISD(T)/CBS level of theory. High-pressure limiting rate constants of 39 reaction channels are obtained using conventional transition state theory with asymmetric Eckart tunneling corrections in the temperature range 298.15-2000 K. Reaction rate rules for H-atom abstraction by the H atom from alkyl cyclohexanes on primary, secondary and tertiary carbon sites on both the side chain and ring are provided. The obtained rate constants are given by the Arrhenius expression in the temperature range 500-2000 K, which can be used for the combustion kinetics model development for alkyl cyclohexanes.

5.
Phys Chem Chem Phys ; 2024 Jun 24.
Article En | MEDLINE | ID: mdl-38912566

Dislocation phenomena in solids under simple shear stress are theoretically addressed with the free volume concept and Eyring's rate process theory for obtaining a generic and unified description. The obtained equations do not have any restrictions to specific materials and are compared with various theories and empirical equations like the Hall-Petch and its inverse forms. Moreover, our equations are used to fit experimental data of mechanical properties and dislocation density against grain sizes available in the literature. A good agreement with observations is achieved, indicating that our theoretical framework is sound. Our findings provide a theoretical foundation for the very common dislocation phenomena observed among many solid materials including pure metals, metallic alloys, ceramics, and even geological scale entities, potentially clearing out many inconsistencies and puzzles in the literature.

6.
Magn Reson Med ; 2024 May 09.
Article En | MEDLINE | ID: mdl-38725132

PURPOSE: To investigate the feasibility of diffusion tensor brain imaging at 0.55T with comparisons against 3T. METHODS: Diffusion tensor imaging data with 2 mm isotropic resolution was acquired on a cohort of five healthy subjects using both 0.55T and 3T scanners. The signal-to-noise ratio (SNR) of the 0.55T data was improved using a previous SNR-enhancing joint reconstruction method that jointly reconstructs the entire set of diffusion weighted images from k-space using shared-edge constraints. Quantitative diffusion tensor parameters were estimated and compared across field strengths. We also performed a test-retest assessment of repeatability at each field strength. RESULTS: After applying SNR-enhancing joint reconstruction, the diffusion tensor parameters obtained from 0.55T data were strongly correlated ( R 2 ≥ 0 . 70 $$ {R}^2\ge 0.70 $$ ) with those obtained from 3T data. Test-retest analysis showed that SNR-enhancing reconstruction improved the repeatability of the 0.55T diffusion tensor parameters. CONCLUSION: High-resolution in vivo diffusion MRI of the human brain is feasible at 0.55T when appropriate noise-mitigation strategies are applied.

8.
Int J Mol Sci ; 25(7)2024 Mar 30.
Article En | MEDLINE | ID: mdl-38612685

Endometriosis is a complex gynecological disease that affects more than 10% of women in their reproductive years. While surgery can provide temporary relief from women's pain, symptoms often return in as many as 75% of cases within two years. Previous literature has contributed to theories about the development of endometriosis; however, the exact pathogenesis and etiology remain elusive. We conducted a preliminary investigation into the influence of primary endometrial cells (ECs) on the development and progression of endometriosis. In vitro studies, they were involved in inducing Lipopolysaccharide (LPS) in rat-isolated primary endometrial cells, which resulted in increased nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) mRNA gene expression (quantitative polymerase chain reaction analysis, qPCR) and protein expression (western blot analysis). Additionally, in vivo studies utilized autogenic and allogeneic transplantations (rat to rat) to investigate endometriosis-like lesion cyst size, body weight, protein levels (immunohistochemistry), and mRNA gene expression. These studies demonstrated that estrogen upregulates the gene and protein regulation of cytoskeletal (CK)-18, transforming growth factor-ß (TGF-ß), VEGF, and tumor necrosis factor (TNF)-α, particularly in the peritoneum. These findings may influence cell proliferation, angiogenesis, fibrosis, and inflammation markers. Consequently, this could exacerbate the occurrence and progression of endometriosis.


Endometriosis , Female , Humans , Animals , Rats , Vascular Endothelial Growth Factor A/genetics , Cell Proliferation , Cytoskeleton , RNA, Messenger
9.
J Am Chem Soc ; 146(15): 10833-10846, 2024 Apr 17.
Article En | MEDLINE | ID: mdl-38578848

Multiexciton in singlet exciton fission represents a critical quantum state with significant implications for both solar cell applications and quantum information science. Two distinct fields of interest explore contrasting phenomena associated with the geminate triplet pair: one focusing on the persistence of long-lived correlation and the other emphasizing efficient decorrelation. Despite the pivotal nature of multiexciton processes, a comprehensive understanding of their dependence on the structural and spin properties of materials is currently lacking in experimental realizations. To address this gap in knowledge, molecular engineering was employed to modify the TIPS-tetracene structures, enabling an investigation of the structure-property relationships in spin-related multiexciton processes. In lieu of the time-resolved electron paramagnetic resonance technique, two time-resolved magneto-optical spectroscopies were implemented for quantitative analysis of spin-dependent multiexciton dynamics. The utilization of absorption and fluorescence signals as complementary optical readouts, in the presence of a magnetic field, provided crucial insights into geminate triplet pair dynamics. These insights encompassed the duration of multiexciton correlation and the involvement of the spin state in multiexciton decorrelation. Furthermore, simulations based on our kinetic models suggested a role for quintet dilution in multiexciton dynamics, surpassing the singlet dilution principle established by the Merrifield model. The integration of intricate model structures and time-resolved magneto-optical spectroscopies served to explicitly elucidate the interplay between structural and spin properties in multiexciton processes. This comprehensive approach not only contributes to the fundamental understanding of these processes but also aligns with and reinforces previous experimental studies of solid states and theoretical assessments.

10.
Article En | MEDLINE | ID: mdl-38518984

Benzophenone chemicals (BPs) have been developed to prevent the adverse effects of UV radiation and they are widely contaminated. 11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) catalyze the conversion of inactive glucocorticoid to active glucocorticoid, playing critical role in many physiological function. However, the direct effect of BPs on human, pig, rat, and mouse 11ß-HSD1 remains unclear. In this study, we screened the inhibitory strength of 12 BPs on 4 species, and performed the structure-activity relationship (SAR) and in silico docking analysis. The inhibitory potency of BPs was: for human 11ß-HSD1, BP6 (IC50 = 18.76 µM) > BP8 (40.84 µM) > BP (88.89 µM) > other BPs; for pig 11ß-HSD1, BP8 (45.57 µM) > BP6 (59.44 µM) > BP2 (65.12 µM) > BP (135.56 µM) > other BPs; for rat 11ß-HSD1, BP7 (67.17 µM) > BP (68.83 µM) > BP8 (133.04 µM) > other BPs; and for mouse 11ß-HSD1, BP8 (41.41 µM) > BP (50.61 µM) > other BPs. These BP chemicals were mixed/competitive inhibitors of these 11ß-HSD1 enzymes. The 2,2'-dihydroxy substitutions in two benzene rings play a key role in enhancing the effectiveness of inhibiting 11ß-HSD1, possibly via increasing hydrogen bond interactions. Docking analysis shows that these BPs bind to NADPH/glucocorticoid binding sites and forms hydrogen bonds with catalytic residues Ser and/or Tyr. In conclusion, this study demonstrates that BP chemicals can inhibit 11ß-HSD1 from 4 species, and there are subtle species-dependent difference in the inhibitory strength and structural variations of BPs.


11-beta-Hydroxysteroid Dehydrogenase Type 1 , Benzophenones , Molecular Docking Simulation , Animals , Benzophenones/chemistry , Benzophenones/pharmacology , 11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , 11-beta-Hydroxysteroid Dehydrogenase Type 1/chemistry , Humans , Structure-Activity Relationship , Rats , Mice , Swine , Sunscreening Agents/chemistry , Sunscreening Agents/pharmacology , Sunscreening Agents/toxicity , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Species Specificity , Ultraviolet Rays
11.
PLoS Comput Biol ; 20(3): e1011942, 2024 Mar.
Article En | MEDLINE | ID: mdl-38498530

Reducing contributions from non-neuronal sources is a crucial step in functional magnetic resonance imaging (fMRI) connectivity analyses. Many viable strategies for denoising fMRI are used in the literature, and practitioners rely on denoising benchmarks for guidance in the selection of an appropriate choice for their study. However, fMRI denoising software is an ever-evolving field, and the benchmarks can quickly become obsolete as the techniques or implementations change. In this work, we present a denoising benchmark featuring a range of denoising strategies, datasets and evaluation metrics for connectivity analyses, based on the popular fMRIprep software. The benchmark prototypes an implementation of a reproducible framework, where the provided Jupyter Book enables readers to reproduce or modify the figures on the Neurolibre reproducible preprint server (https://neurolibre.org/). We demonstrate how such a reproducible benchmark can be used for continuous evaluation of research software, by comparing two versions of the fMRIprep. Most of the benchmark results were consistent with prior literature. Scrubbing, a technique which excludes time points with excessive motion, combined with global signal regression, is generally effective at noise removal. Scrubbing was generally effective, but is incompatible with statistical analyses requiring the continuous sampling of brain signal, for which a simpler strategy, using motion parameters, average activity in select brain compartments, and global signal regression, is preferred. Importantly, we found that certain denoising strategies behave inconsistently across datasets and/or versions of fMRIPrep, or had a different behavior than in previously published benchmarks. This work will hopefully provide useful guidelines for the fMRIprep users community, and highlight the importance of continuous evaluation of research methods.


Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Magnetic Resonance Imaging/methods , Image Processing, Computer-Assisted/methods , Artifacts , Brain/diagnostic imaging , Brain/physiology , Brain Mapping/methods
12.
Cell ; 187(5): 1296-1311.e26, 2024 Feb 29.
Article En | MEDLINE | ID: mdl-38428397

Most membrane proteins are modified by covalent addition of complex sugars through N- and O-glycosylation. Unlike proteins, glycans do not typically adopt specific secondary structures and remain very mobile, shielding potentially large fractions of protein surface. High glycan conformational freedom hinders complete structural elucidation of glycoproteins. Computer simulations may be used to model glycosylated proteins but require hundreds of thousands of computing hours on supercomputers, thus limiting routine use. Here, we describe GlycoSHIELD, a reductionist method that can be implemented on personal computers to graft realistic ensembles of glycan conformers onto static protein structures in minutes. Using molecular dynamics simulation, small-angle X-ray scattering, cryoelectron microscopy, and mass spectrometry, we show that this open-access toolkit provides enhanced models of glycoprotein structures. Focusing on N-cadherin, human coronavirus spike proteins, and gamma-aminobutyric acid receptors, we show that GlycoSHIELD can shed light on the impact of glycans on the conformation and activity of complex glycoproteins.


Glycoproteins , Molecular Dynamics Simulation , Humans , Cryoelectron Microscopy , Glycoproteins/chemistry , Glycosylation , Polysaccharides/chemistry
13.
Food Chem Toxicol ; 186: 114489, 2024 Apr.
Article En | MEDLINE | ID: mdl-38360388

Curcuminoids have many pharmacological effects. They or their metabolites may have side effects by suppressing 17ß-hydroxysteroid dehydrogenase 3 (17ß-HSD3). Herein, we investigated the inhibition of curcuminoids and their metabolites on human and rat 17ß-HSD3 and analyzed their structure-activity relationship (SAR) and performed in silico docking. Curcuminoids and their metabolites ranked in terms of IC50 values against human 17ß-HSD3 were bisdemethoxycurcumin (0.61 µM) > curcumin (8.63 µM) > demethoxycurcumin (9.59 µM) > tetrahydrocurcumin (22.04 µM) > cyclocurcumin (29.14 µM), and those against rat 17ß-HSD3 were bisdemethoxycurcumin (3.94 µM) > demethoxycurcumin (4.98 µM) > curcumin (9.62 µM) > tetrahydrocurcumin (45.82 µM) > cyclocurcumin (143.5 µM). The aforementioned chemicals were mixed inhibitors for both enzymes. Molecular docking analysis revealed that they bind to the domain between the androstenedione and NADPH active sites of 17ß-HSD3. Bivariate correlation analysis showed a positive correlation between LogP and pKa of curcumin derivatives with their IC50 values. Additionally, a 3D-QSAR analysis revealed that a pharmacophore model consisting of three hydrogen bond acceptor regions and one hydrogen bond donor region provided a better fit for bisdemethoxycurcumin compared to curcumin. In conclusion, curcuminoids and their metabolites possess the ability to inhibit androgen biosynthesis by directly targeting human and rat 17ß-HSD3. The inhibitory strength of these compounds is influenced by their lipophilicity and ionization characteristics.


17-Hydroxysteroid Dehydrogenases , Curcumin , Curcumin/analogs & derivatives , Diarylheptanoids , Pyrans , Humans , Rats , Animals , Curcumin/pharmacology , Quantitative Structure-Activity Relationship , Molecular Docking Simulation , Structure-Activity Relationship
14.
Materials (Basel) ; 17(4)2024 Feb 07.
Article En | MEDLINE | ID: mdl-38399061

This work develops a three-dimensional (3D) weak formulation, based on the consistent couple stress theory (CCST), for analyzing the size-dependent dynamic instability behavior of simply-supported, functionally graded (FG) cylindrical microshells that are subjected to combinations of periodic axial compression and external pressure. In our formulation, the microshells are artificially divided into nl layers. The displacement components of each individual layer are selected as the primary variables, which are expanded as a double Fourier series in the in-plane domain and are interpolated with Hermitian C2 polynomials in the thickness direction. Incorporating the layer-wise displacement models into our weak formulation, we develop a Hermitian C2 finite layer method (FLM) for addressing the current issue. The accuracy and the convergence rate of our Hermitian C2 FLM are validated by comparing the solutions it produces with the accurate two-dimensional solutions of critical loads and critical pressures of FG cylindrical macroshells and single-walled carbon nanotubes, which were reported in the literature. The numerical results show the effects of the material length-scale parameter, the inhomogeneity index, the radius-to-thickness and length-to-radius ratios, the load magnitude ratio, and the static and dynamic load factors on the first principal and first secondary instability regions of parametric resonance of simply-supported FG cylindrical microshells are significant.

15.
J Dent Sci ; 19(1): 404-410, 2024 Jan.
Article En | MEDLINE | ID: mdl-38303874

Background/purpose: Temporary anchorage devices (TADs) are widely used in contemporary orthodontic treatments for anchorage purposes. This research aimed to investigate orthodontists' attitude toward temporary anchorage devices (TADs) by surveying their TAD usage frequency and pricing and to identify factors influencing TAD usage frequency and pricing. Materials and methods: A structured, self-administered questionnaire with a total of 26 questions was randomly distributed to members of the Taiwanese Association of Orthodontics at the annual orthodontic meeting. The questionnaire comprised 6 questions on demographics, 10 questions on work patterns and patient type, and 10 questions on orthodontic technique. Responses were analyzed using a Pearson chi-Square test to identify factors of interest. Results: Factors associated with TAD usage frequency included degree of income satisfaction, number of working hours per week, and proportion of extraction-based treatments in treatment plans. Factors associated with TAD pricing included orthodontist age, geographic region of practice, and adult treatment fee. Conclusion: More Taiwanese orthodontists use TADs compared with orthodontists in other countries. TADs have become universally accepted, but practitioners use them selectively. The main factor influencing TAD usage frequency was the proportion of extraction-based treatments in treatment plans, and those influencing TAD were orthodontist age, geographic region of practice, and adult treatment fee. These findings may be applicable to other parts of the world and should be investigated at an international level.

16.
J Mol Biol ; 436(4): 168438, 2024 02 15.
Article En | MEDLINE | ID: mdl-38185323

A mutant of ubiquitin C-terminal hydrolase L1 (UCHL1) detected in early-onset neurodegenerative patients, UCHL1R178Q, showed higher catalytic activity than wild-type UCHL1 (UCHL1WT). Lying within the active-site pocket, the arginine is part of an interaction network that holds the catalytic histidine in an inactive arrangement. However, the structural basis and mechanism of enzymatic activation upon glutamine substitution was not understood. We combined X-ray crystallography, protein nuclear magnetic resonance (NMR) analysis, enzyme kinetics, covalent inhibition analysis, and biophysical measurements to delineate activating factors in the mutant. While the crystal structure of UCHL1R178Q showed nearly the same arrangement of the catalytic residues and active-site pocket, the mutation caused extensive alteration in the chemical environment and dynamics of more than 30 residues, some as far as 15 Å away from the site of mutation. Significant broadening of backbone amide resonances in the HSQC spectra indicates considerable backbone dynamics changes in several residues, in agreement with solution small-angle X-ray scattering (SAXS) analyses which indicate an overall increase in protein flexibility. Enzyme kinetics show the activation is due to a kcat effect despite a slightly weakened substrate affinity. In line with this, the mutant shows a higher second-order rate constant (kinact/Ki) in a reaction with a substrate-derived irreversible inhibitor, Ub-VME, compared to the wild-type enzyme, an observation indicative of a more reactive catalytic cysteine in the mutant. Together, the observations underscore structural plasticity as a factor contributing to enzyme kinetic behavior which can be modulated through mutational effects.


Catalytic Domain , Cysteine , Neurodegenerative Diseases , Ubiquitin Thiolesterase , Humans , Binding Sites/genetics , Cysteine/chemistry , Cysteine/genetics , Kinetics , Mutagenesis, Site-Directed , Nuclear Magnetic Resonance, Biomolecular , Scattering, Small Angle , Ubiquitin Thiolesterase/chemistry , Ubiquitin Thiolesterase/genetics , X-Ray Diffraction , Neurodegenerative Diseases/genetics
17.
Gastroenterology ; 166(4): 605-619, 2024 04.
Article En | MEDLINE | ID: mdl-38176660

BACKGROUND & AIMS: We aimed to assess the secular trend of the global prevalence of Helicobacter pylori (H pylori) infection in adults and children/adolescents and to show its relation to that of gastric cancer incidence. METHODS: We performed a systematic review and meta-analysis to calculate overall prevalence, adjusted by multivariate meta-regression analysis. The incidence rates of gastric cancer were derived from the Global Burden of Disease Study and Cancer Incidence in Five Continents. RESULTS: Of the 16,976 articles screened, 1748 articles from 111 countries were eligible for analysis. The crude global prevalence of H pylori has reduced from 52.6% (95% confidence interval [CI], 49.6%-55.6%) before 1990 to 43.9% (95% CI, 42.3%-45.5%) in adults during 2015 through 2022, but was as still as high as 35.1% (95% CI, 30.5%-40.1%) in children and adolescents during 2015 through 2022. Secular trend and multivariate regression analyses showed that the global prevalence of H pylori has declined by 15.9% (95% CI, -20.5% to -11.3%) over the last 3 decades in adults, but not in children and adolescents. Significant reduction of H pylori prevalence was observed in adults in the Western Pacific, Southeast Asian, and African regions. However, H pylori prevalence was not significantly reduced in children and adolescents in any World Health Organization regions. The incidence of gastric cancer has decreased globally and in various countries where the prevalence of H pylori infection has declined. CONCLUSIONS: The global prevalence of H pylori infection has declined during the last 3 decades in adults, but not in children and adolescents. The results raised the hypothesis that the public health drive to reduce the prevalence of H pylori as a strategy to reduce the incidence of gastric cancer in the population should be confirmed in large-scale clinical trials.


Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Adult , Child , Adolescent , Humans , Incidence , Stomach Neoplasms/epidemiology , Stomach Neoplasms/etiology , Helicobacter Infections/drug therapy , Prevalence
18.
Food Chem Toxicol ; 183: 114257, 2024 Jan.
Article En | MEDLINE | ID: mdl-38040240

The use of alternative substances to replace bisphenol A (BPA) has been encouraged. The objective of this study was to evaluate the effects of BPA and 9 BPA alternatives on human and rat aromatase (CYP19A1) in human and rat placental microsomes. The results revealed that bisphenol A, AP, B, C, E, F, FL, S, and Z, and 4,4'-thiodiphenol (TDP) inhibited human CYP19A1 and bisphenol A, AP, B, C, FL, Z, and TDP inhibited rat CYP19A1. The IC50 values of human CYP19A1 ranged from 3.3 to 172.63 µM and those of rat CYP19A1 ranged from 2.20 to over 100 µM. BPA alternatives were mixed/competitive inhibitors and inhibited estradiol production in BeWo placental cells. Molecular docking analysis showed that BPA alternatives bind to the domain between heme and steroid and form a hydrogen bond with catalytic residue Met374. Pharmacophore analysis showed that there were one hydrogen bond donor, one hydrophobic region, and one ring aromatic hydrophobic region. Bivariate correlation analysis showed that molecular weight, alkyl atom weight, and LogP of BPA alternatives were inversely correlated with their IC50 values. In conclusion, BPA alternatives can inhibit human and rat CYP19A1 and the lipophilicity and the substituted alkyl size determines their inhibitory strength.


Aromatase , Placenta , Humans , Pregnancy , Female , Animals , Rats , Aromatase/metabolism , Placenta/metabolism , Molecular Docking Simulation , Cell Line, Tumor , Quantitative Structure-Activity Relationship , Cytochrome P-450 CYP1A1/metabolism , Benzhydryl Compounds/pharmacology , DNA-Binding Proteins
19.
Nano Lett ; 24(1): 67-73, 2024 Jan 10.
Article En | MEDLINE | ID: mdl-38149785

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces.

20.
ACS Appl Mater Interfaces ; 16(1): 1705-1711, 2024 Jan 10.
Article En | MEDLINE | ID: mdl-38145463

Two-dimensional (2D) metal nitrides have garnered significant interest due to their potential applications in future electronics and quantum systems. However, the synthesis of such materials with sufficient uniformity and at relevant scales remains an unaddressed challenge. This study demonstrates the potential of confined growth to control and enhance the morphology of 2D metal nitrides. By restricting the reaction volume of vapor-liquid-solid reactions, an enhanced precursor concentration was achieved that reduces the nucleation density, resulting in larger grain sizes and suppression of multilayer growth. Detailed characterization reveals the importance of balancing the energetic and kinetic aspects of tungsten nitride formation toward this ability. The introduction of a promoter enabled the realization of large-scale, single-layer tungsten nitride with a uniform and high interfacial quality. Finally, our advance in morphology control was applied to the production of edge-enriched 2D tungsten nitrides with significantly enhanced hydrogen evolution ability, as indicated by an unprecedented Tafel slope of 55 mV/dec.

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