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1.
Environ Res ; 259: 119523, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38960352

RÉSUMÉ

Strengthening rhizosphere effects to enhance pollutant removal is a hotspot of constructed wetlands (CWs) research in recent years, and improving the root traits and metabolic capacity of macrophytes is crucial for strengthening rhizosphere effects. In the field experiment, two types of subsurface flow (SSF) CWs (CW10 and CW20, with substrate depths of 10 and 20 cm, respectively) under the vertical spatial stress of roots (VSSR) and two types of non-VSSR SSF CWs (CW40 and CW60) were adopted with Typha orientalis as cultivated plants to investigate the variability of root development, metabolism, and pollutant removal at different substrate depths. VSSR induced substantial redundant root development, which significantly increased root-shoot ratio, fine and lateral root biomass, root porosity, and root activity, with lateral and fine root biomass of CW20 reaching 409.17 and 237.42 g/m2, respectively, which were 3.18 and 5.28 times those of CW60. The radical oxygen loss (ROL) and dissolved organic carbon (DOC) levels of CW20 single plant were 1.36 and 4.57 times higher than those of CW60, respectively, and more types of root exudates were determined (e.g., aldehydes, ketones and amides). More aerobic heterotrophs (e.g., Massilia, Planomicrobium), nitrification bacteria (e.g., Ellin6067, Nitrospira), aerobic denitrification bacteria (e.g., Bacillu, Chryseobacterium, Pseudomonas) and denitrification phosphorus accumulating organisms (e.g., Flavobacterium) were enriched in the rhizosphere of CW20. This changed the main transformation pathways of pollutants and enhanced the removal of pollutants, with the COD, TN and TP average removal rates of CW20 increasing by 9.99%, 13.28% and 8.92%, respectively, compared with CW60. The ideotype root system architecture CW (RSACW; CW20) constructed in this study, which consists of a large number of fine and lateral roots, can stimulate more efficient rhizosphere effects stably and continuously.

2.
Heliyon ; 10(12): e32816, 2024 Jun 30.
Article de Anglais | MEDLINE | ID: mdl-38975197

RÉSUMÉ

Metagenomic next-generation sequencing (mNGS) has revolutionized the detection of pathogens, particularly in immunocompromised individuals such as pediatric patients undergoing intensive chemotherapy and hematopoietic stem cell transplantation. This study aims to explore the impact of neutrophil count on the diagnostic efficacy of mNGS in diagnosing infections in pediatric patients with febrile diseases. We conducted a retrospective analysis of pediatric patients with febrile diseases in the hematology/oncology department from January 2019 to September 2022. The study included 387 patients with 516 febrile episodes. Analyzing data from 516 pediatric cases, our study found that 70.7 % had febrile neutropenia (FN) and 29.3 % had febrile without neutropenia (FWN). mNGS demonstrated a high positive detection rate of 84.9 %, compared to 29.7 % for conventional microbiological tests (CMT). While the positive detection rates of mNGS were similar in both FN and FWN groups, bacterial pathogens were more frequently detected in FN patients. Furthermore, the rate of identifying a "probable" microbial etiology was lower in the FN group (46.8 %) compared to the FWN group (65.6 %, p<0.001). When analyzing the types of organisms and specimens, the "probable" identification rates were particularly lower for viruses and fungi detected by mNGS, as well as in blood and nasopharyngeal swab samples. These findings underscore the significant influence of neutrophil counts on mNGS results in pediatric febrile patients and highlight the necessity for tailored diagnostic approaches in this population.

3.
Heliyon ; 10(11): e31677, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38841453

RÉSUMÉ

Background: Metagenomic next-generation sequencing (mNGS) of plasma DNA has become an attractive diagnostic method for infectious diseases; however, the rate of false-positive results is high. This study aims to evaluate the diagnostic accuracy of mNGS in plasma versus blood cell samples for immunocompromised children with febrile diseases. Methods: The results of conventional microbiological test (CMT) and mNGS using plasma and blood cells in 106 patients with 128 episodes of febrile diseases from the Department of Hematology/Oncology were analyzed and described. Results: The positivity rates for CMT and mNGS of plasma and blood cells were 35.9 %, 84.4 % and 46.9 %, respectively (P < 0.001). Notably, mNGS identified multiple pathogens in a single specimen in 68.5 % of plasma samples and 38.3 % of blood cell samples (P < 0.001). Furthermore, plasma and blood cell mNGS identified causative pathogens in 58 and 46 cases, accounting for 53.7 % and 76.7 % of the mNGS-positive cases for each sample type, respectively (P = 0.002). By integrating results from both plasma and blood cell samples, causative pathogens were identified in 77 cases (60.2 %), enhancing sensitivity to 87.5 % but reducing specificity to 15.0 %, compared to plasma (65.9 % sensitivity and 20.0 % specificity) and blood cell samples (52.3 % sensitivity and 80.0 % specificity). Conclusions: mNGS of plasma is sensitive but has a high false-positive rate, while mNGS of blood cells has low sensitivity but higher specificity.

4.
Cancer Sci ; 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38932450

RÉSUMÉ

Atypical L858R or other L858X mutations in the epidermal growth factor receptor (EGFR) gene, beyond the classical EGFRL858R mutation caused by c.2573 T > G, have been identified in non-small cell lung cancer (NSCLC), yet their genomic features and survival benefits with EGFR tyrosine kinase inhibitor (TKI) treatment have not been fully explored. We retrospectively enrolled 489 NSCLC patients with baseline tumor tissue/plasma samples carrying uncommon EGFRL858R (N = 124), EGFRL858Q/M (N = 17), or classical EGFRL858R mutations (N = 348). The comparison of molecular features was performed using treatment-naïve tumor tissues. Survival benefits and resistance mechanisms of first-line EGFR TKI treatment were studied in an advanced disease subcohort. NSCLCs harboring uncommon EGFRL858R had lower TP53 mutation prevalence (p = 0.04) and chromosome instability scores (p = 0.02) than those with classical EGFRL858R. Concomitant EGFRL861Q mutations were enriched in NSCLCs with EGFRL858Q/M (p < 0.01), with cooccurrence in those carrying EGFRL858M. Patients with uncommon EGFRL858R experienced improved progression-free survival (PFS) compared to those with classical EGFRL858R (median: 13.0 vs. 10.0 months, hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.41-0.80). The association remained significant when adjusting for sex, age, histological subtype, TKI category, and anti-vascular therapy (HR: 0.55, 95% CI: 0.39-0.77). Furthermore, EGFRL858Q/M patients showed enhanced first-line PFS (vs. classical EGFRL858R, HR: 0.26, 95% CI: 0.10-0.67), potentially benefiting more from afatinib. Additionally, NSCLCs with uncommon EGFRL858R and classical EGFRL858R had similar resistance profiles to EGFR TKIs. In conclusion, NSCLCs carrying atypical EGFR L858 aberrations, which had fewer TP53 mutations and higher chromosome stability, exhibited improved PFS under first-line EGFR TKIs than those with the classical EGFRL858R.

5.
JAMA Netw Open ; 7(5): e2413708, 2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38809553

RÉSUMÉ

Importance: Helicobacter pylori treatment and nutrition supplementation may protect against gastric cancer (GC), but whether the beneficial effects only apply to potential genetic subgroups and whether high genetic risk may be counteracted by these chemoprevention strategies remains unknown. Objective: To examine genetic variants associated with the progression of gastric lesions and GC risk and to assess the benefits of H pylori treatment and nutrition supplementation by levels of genetic risk. Design, Setting, and Participants: This cohort study used follow-up data of the Shandong Intervention Trial (SIT, 1989-2022) and China Kadoorie Biobank (CKB, 2004-2018) in China. Based on the SIT, a longitudinal genome-wide association study was conducted to identify genetic variants for gastric lesion progression. Significant variants were examined for incident GC in a randomly sampled set of CKB participants (set 1). Polygenic risk scores (PRSs) combining independent variants were assessed for GC risk in the remaining CKB participants (set 2) and in an independent case-control study in Linqu. Exposures: H pylori treatment and nutrition supplementation. Main Outcomes and Measures: Primary outcomes were the progression of gastric lesions (in SIT only) and the risk of GC. The associations of H pylori treatment and nutrition supplementation with GC were evaluated among SIT participants with different levels of genetic risk. Results: Our analyses included 2816 participants (mean [SD] age, 46.95 [9.12] years; 1429 [50.75%] women) in SIT and 100 228 participants (mean [SD] age, 53.69 [11.00] years; 57 357 [57.23%] women) in CKB, with 147 GC cases in SIT and 825 GC cases in CKB identified during follow-up. A PRS integrating 12 genomic loci associated with gastric lesion progression and incident GC risk was derived, which was associated with GC risk in CKB (highest vs lowest decile of PRS: hazard ratio [HR], 2.54; 95% CI, 1.80-3.57) and further validated in the analysis of 702 case participants and 692 control participants (mean [SD] age, 54.54 [7.66] years; 527 [37.80%] women; odds ratio, 1.83; 95% CI, 1.11-3.05). H pylori treatment was associated with reduced GC risk only for individuals with high genetic risk (top 25% of PRS: HR, 0.45; 95% CI, 0.25-0.82) but not for those with low genetic risk (HR, 0.81; 95% CI, 0.50-1.34; P for interaction = .03). Such effect modification was not found for vitamin (P for interaction = .93) or garlic (P for interaction = .41) supplementation. Conclusions and Relevance: The findings of this cohort study indicate that a high genetic risk of GC may be counteracted by H pylori treatment, suggesting primary prevention could be tailored to genetic risk for more effective prevention.


Sujet(s)
Prédisposition génétique à une maladie , Infections à Helicobacter , Helicobacter pylori , Tumeurs de l'estomac , Humains , Tumeurs de l'estomac/génétique , Tumeurs de l'estomac/épidémiologie , Femelle , Mâle , Adulte d'âge moyen , Infections à Helicobacter/traitement médicamenteux , Infections à Helicobacter/complications , Chine/épidémiologie , Étude d'association pangénomique , Études cas-témoins , Adulte , Facteurs de risque , Compléments alimentaires , Études de cohortes , Sujet âgé , Antibactériens/usage thérapeutique
6.
Eur J Med Chem ; 273: 116519, 2024 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-38795519

RÉSUMÉ

Anticancer peptides (ACPs) have regarded as a new generation of promising antitumor drugs due to the unique mode of action. The main challenge is to develop potential anticancer peptides with satisfied antitumor activity and low toxicity. Here, a series of new α-helical anticancer peptides were designed and synthesized based on the regular repeat motif KLLK. The optimal peptides 14E and 14Aad were successfully derived from the new short α-helical peptide KL-8. Our results demonstrated that 14E and 14Aad had good antitumor activity and low toxicity, exhibiting excellent selectivity index. This result highlighted that the desirable modification position and appropriate hydrophobic side-chain structure of acidic amino acids played critical roles in regulating the antitumor activity/toxicity of new peptides. Further studies indicated that they could induce tumor cell death via the multiple actions of efficient membrane disruption and intracellular mechanisms, displaying apparent superiority in combination with PTX. In addition, the new peptides 14E and 14Aad showed excellent antitumor efficacy in vivo and low toxicity in mice compared to KL-8 and PTX. Particularly, 14Aad with the longer side chain at the 14th site exhibited the best therapeutic performance. In conclusion, our work provided a new avenue to develop promising anticancer peptides with good selectivity for tumor therapy.


Sujet(s)
Antinéoplasiques , Prolifération cellulaire , Conception de médicament , Tests de criblage d'agents antitumoraux , Peptides , Antinéoplasiques/pharmacologie , Antinéoplasiques/composition chimique , Antinéoplasiques/synthèse chimique , Animaux , Humains , Souris , Peptides/composition chimique , Peptides/pharmacologie , Peptides/synthèse chimique , Relation structure-activité , Prolifération cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Structure moléculaire , Lignée cellulaire tumorale , Souris de lignée BALB C , Apoptose/effets des médicaments et des substances chimiques , Femelle
7.
Anal Biochem ; 691: 115556, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38705226

RÉSUMÉ

we developed an effective protein precipitation method for determination of levamlodipine in human plasma using LC-MS/MS. Sample extraction was carried out by using liquid-liquid extraction in 96-well plate format. (S)-Amlodipine-d4 was used as internal standard (IS). The chromatographic separation was achieved using Philomen Chiral MX (2) column (3 µm, 2.1 × 100 mm). Mobile phase A was comprised of Acetonitrile (ACN), Mono ethanol amine (MEA) and Iso-Propyl alcohol (IPA) (1000:1:10, v/v/v), Mobile phase B was IPA-ACN (2:1, v/v). The flow rate was 0.4 mL/min. The total run time of each sample was 4.0 min with gradient elution. LC-MS/MS spectra were generated in positive ion mode, and multiple reaction monitoring (MRM) was used to detect the following transitions: m/z 409.20 â†’ 238.15 for levamlodipine and 415.25 â†’ 240.20 for (S)-Amlodipine-d4 (the IS). The method was linear from 50 to 10000 pg/mL(R2=0.9988489),and the lower limit of quantification (LLOQ) was 50 pg/mL. This method was applied to a bioequivalence study of levamlodipine.


Sujet(s)
Acide nicotinique/analogues et dérivés , Spectrométrie de masse en tandem , Humains , Spectrométrie de masse en tandem/méthodes , Chromatographie en phase liquide/méthodes , Dihydropyridines/sang , Dihydropyridines/pharmacocinétique , Dihydropyridines/composition chimique , Extraction liquide-liquide , Limite de détection , Amlodipine/sang , Amlodipine/pharmacocinétique ,
8.
Eur J Med Chem ; 271: 116451, 2024 May 05.
Article de Anglais | MEDLINE | ID: mdl-38691892

RÉSUMÉ

The potent antibacterial activity and low resistance of antimicrobial peptides (AMPs) render them potential candidates for treating multidrug-resistant bacterial infections. Herein, a minimalist design strategy was proposed employing the "golden partner" combination of arginine (R) and tryptophan (W), along with a dendritic structure to design AMPs. By extension, the α/ε-amino group and the carboxyl group of lysine (K) were utilized to link R and W, forming dendritic peptide templates αRn(εRn)KWm-NH2 and αWn(εWn)KRm-NH2, respectively. The corresponding linear peptide templates R2nKWm-NH2 and W2nKRm-NH2 were used as controls. Their physicochemical properties, activity, toxicity, and stability were compared. Among these new peptides, the dendritic peptide R2(R2)KW4 was screened as a prospective candidate owing to its preferable antibacterial properties, biocompatibility, and stability. Additionally, R2(R2)KW4 not only effectively restrained the progression of antibiotic resistance, but also demonstrated synergistic utility when combined with conventional antibiotics due to its unique membrane-disruptive mechanism. Furthermore, R2(R2)KW4 possessed low toxicity (LD50 = 109.31 mg/kg) in vivo, while efficiently clearing E. coli in pulmonary-infected mice. In conclusion, R2(R2)KW4 has the potential to become an antimicrobial regent or adjuvant, and the minimalist design strategy of dendritic peptides provides innovative and encouraging thoughts in designing AMPs.


Sujet(s)
Antibactériens , Arginine , Tests de sensibilité microbienne , Tryptophane , Tryptophane/composition chimique , Tryptophane/pharmacologie , Animaux , Arginine/composition chimique , Arginine/pharmacologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Antibactériens/synthèse chimique , Souris , Peptides antimicrobiens/composition chimique , Peptides antimicrobiens/pharmacologie , Peptides antimicrobiens/synthèse chimique , Relation structure-activité , Structure moléculaire , Membrane cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Infections bactériennes/traitement médicamenteux , Humains , Escherichia coli/effets des médicaments et des substances chimiques
9.
Curr Protoc ; 4(4): e1033, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38652202

RÉSUMÉ

Prostate cancer is a leading diagnosis and major cause of cancer-related deaths in men worldwide. As a typical hormone-responsive disease, prostate cancer is commonly managed with androgen deprivation therapy (ADT) to curb its progression and potential metastasis. Unfortunately, progression to castration-resistant prostate cancer (CRPC), a notably more aggressive phase of the disease, occurs within a timeframe of 2-3 years following ADT. Enzalutamide, a recognized androgen receptor (AR) antagonist, has been employed as a standard of care for men with metastatic castration-resistant prostate cancer (mCRPC) since it was first approved in 2012, due to its ability to prolong survival. However, scientific evidence suggests that sustained treatment with AR antagonists may induce acquired AR mutations or splice variants, such as AR F877L, T878A, and H875Y, leading to drug resistance and thereby diminishing the therapeutic efficacy of these agents. Thus, the establishment of prostate cancer models incorporating these particular mutations is essential for developing new therapeutic strategies to overcome such resistance and evaluate the efficacy of next-generation AR-targeting drugs. We have developed a CRISPR (clustered regularly interspaced short palindromic repeats)-based knock-in technology to introduce an additional F877L mutation in AR into the human prostate cell line LNCaP. This article provides comprehensive descriptions of the methodologies for cellular gene editing and establishment of an in vivo model. Using these methods, we successfully identified an enzalutamide-resistant phenotype in both in vitro and in vivo models. We also assessed the efficacy of target protein degraders (TPDs), such as ARV-110 and ARV-667, in both models, and the corresponding validation data are also included here. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Generation of AR F877L-mutated LNCaP cell line using CRISPR technology Basic Protocol 2: Validation of drug resistance in AR F877L-mutated LNCaP cell line using the 2D CTG assay Support Protocol: Testing of sgRNA efficiency in HEK 293 cells Basic Protocol 3: Validation of drug resistance in AR F877L-mutated LNCaP cell line in vivo.


Sujet(s)
Benzamides , Résistance aux médicaments antinéoplasiques , Mutation , Nitriles , 3-Phényl-2-thiohydantoïne , Tumeurs prostatiques résistantes à la castration , Récepteurs aux androgènes , 3-Phényl-2-thiohydantoïne/pharmacologie , 3-Phényl-2-thiohydantoïne/usage thérapeutique , Mâle , Nitriles/usage thérapeutique , Benzamides/usage thérapeutique , Humains , Lignée cellulaire tumorale , Résistance aux médicaments antinéoplasiques/génétique , Résistance aux médicaments antinéoplasiques/effets des médicaments et des substances chimiques , Récepteurs aux androgènes/génétique , Récepteurs aux androgènes/métabolisme , Tumeurs prostatiques résistantes à la castration/traitement médicamenteux , Tumeurs prostatiques résistantes à la castration/génétique , Tumeurs prostatiques résistantes à la castration/anatomopathologie , Animaux , Souris , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique
10.
Mol Imaging Biol ; 2024 Apr 19.
Article de Anglais | MEDLINE | ID: mdl-38641708

RÉSUMÉ

BACKGROUND: Previous studies have initially reported accompanying elevated 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) inflammatory activity in the remote area and its prognostic value after acute myocardial infarction (AMI). Non-invasive characterization of the accompanying inflammation in the remote myocardium may be of potency in guiding future targeted theranostics. [68Ga]Ga-Pentixafor targeting chemokine receptor 4 (CXCR4) on the surface of inflammatory cells is currently one of the promising inflammatory imaging agents. In this study, we sought to focus on the longitudinal evolution of [68Ga]Ga-Pentixafor activities in the remote myocardium following AMI and its association with cardiac function. METHODS: Twelve AMI rats and six Sham rats serially underwent [68Ga]Ga-Pentixafor imaging at pre-operation, and 5, 7, 14 days post-operation. Maximum and mean standard uptake value (SUV) and target-to-background ratio (TBR) were assessed to indicate the uptake intensity. Gated [18F]F-FDG imaging and immunofluorescent staining were performed to obtain cardiac function and responses of pro-inflammatory and reparative macrophages, respectively. RESULTS: The uptake of [68Ga]Ga-Pentixafor in the infarcted myocardium peaked at day 5 (all P = 0.003), retained at day 7 (all P = 0.011), and recovered at day 14 after AMI (P > 0.05), paralleling with the rise-fall pro-inflammatory M1 macrophages (P < 0.05). Correlated with the peak activity in the infarct territory, [68Ga]Ga-Pentixafor uptake in the remote myocardium on day 5 early after AMI significantly increased (AMI vs. Sham: SUVmean, SUVmax, and TBRmean: all P < 0.05), and strongly correlated with contemporaneous EDV and/or ESV (SUVmean and TBRmean: both P < 0.05). The transitory remote activity recovered as of day 7 post-AMI (AMI vs. Sham: P > 0.05). CONCLUSIONS: Corresponding with the peaked [68Ga]Ga-Pentixafor activity in the infarcted myocardium, the activity in the remote region elevated accordingly and led to contemporaneous left ventricular remodelling early after AMI. Further studies are warranted to clarify its clinical application potential.

11.
RSC Adv ; 14(17): 12158-12170, 2024 Apr 10.
Article de Anglais | MEDLINE | ID: mdl-38628484

RÉSUMÉ

Vanadium redox flow battery (VRFB) is a highly suitable technology for energy storage and conversion in the application of decoupling energy and power generation. However, the sluggish reaction kinetics of redox couples is one of the bottlenecks hindering the commercialization of VFFBs. Developing efficient electrode is a promising method to improve the battery performance. In this work, a reduced graphene oxide/Mxene hybrid-decorated graphite felt (rGO/Mxene@GF) is designed to facilitate the kinetics of redox reaction. The electrocatalytic activity and mass transfer of the prepared electrode are investigated through experiment and simulation methods. The results indicate that the favorable mass transfer and the synergistic effect between rGO and Ti3C2Tx Mxene remarkably improve the performance of electrode. The flow cell with rGO/Mxene@GF delivers a good stability up to 100 cycles with a coulombic, voltage, and energy efficiency of 91.6%, 82.7%, and 75.8%, respectively, at a current density of 80 mA cm-2. These findings suggest that the as-prepared rGO/Mxene@GF holds a good application potential in VRFB and provides a promising approach to design efficient electrode for electrochemical devices.

12.
Front Cell Dev Biol ; 12: 1372847, 2024.
Article de Anglais | MEDLINE | ID: mdl-38633106

RÉSUMÉ

Exosomes are small extracellular vesicles secreted by cells, ranging in size from 30 to 150 nm. They contain proteins, nucleic acids, lipids, and other bioactive molecules, which play a crucial role in intercellular communication and material transfer. In tumor immunity, exosomes present various functions while the following two are of great importance: regulating the immune response and serving as delivery carriers. This review starts with the introduction of the formation, compositions, functions, isolation, characterization, and applications of exosomes, and subsequently discusses the current status of exosomes in tumor immunotherapy, and the recent applications of exosome-based tumor immunity regulation and antitumor drug delivery. Finally, current challenge and future prospects are proposed and hope to demonstrate inspiration for targeted readers in the field.

13.
J Tissue Eng ; 15: 20417314241244997, 2024.
Article de Anglais | MEDLINE | ID: mdl-38617462

RÉSUMÉ

The study focused on the effects of a triply periodic minimal surface (TPMS) scaffolds, varying in porosity, on the repair of mandibular defects in New Zealand white rabbits. Four TPMS configurations (40%, 50%, 60%, and 70% porosity) were fabricated with ß-tricalcium phosphate bioceramic via additive manufacturing. Scaffold properties were assessed through scanning electron microscopy and mechanical testing. For proliferation and adhesion assays, mouse bone marrow stem cells (BMSCs) were cultured on these scaffolds. In vivo, the scaffolds were implanted into rabbit mandibular defects for 2 months. Histological staining evaluated osteogenic potential. Moreover, RNA-sequencing analysis and RT-qPCR revealed the significant involvement of angiogenesis-related factors and Hippo signaling pathway in influencing BMSCs behavior. Notably, the 70% porosity TPMS scaffold exhibited optimal compressive strength, superior cell proliferation, adhesion, and significantly enhanced osteogenesis and angiogenesis. These findings underscore the substantial potential of 70% porosity TPMS scaffolds in effectively promoting bone regeneration within mandibular defects.

14.
Article de Anglais | MEDLINE | ID: mdl-38656108

RÉSUMÉ

Topological insulators (TIs) with spin-momentum-locked surface states and considerable spin-to-charge conversion (SCC) efficiency are ideal substitutes for the nonmagnetic layer in the traditional ferromagnetic/nonmagnetic (FM/NM) spintronic terahertz (THz) emitters. Here, the TI/ferrimagnetic structure as an effective polarization tunable THz source is verified by terahertz emission spectroscopy. The emitted THz electric field can be separated into two THz components utilizing their opposite symmetry on pump polarization and the magnetic field. TI not only emits a THz electric field via the linear photogalvanic effect (LPGE) but also serves as the medium of SCC via the inverse Edelstein effect (IEE) in the heterostructure. In addition, the amplitude and polarity of the SCC component can be efficiently manipulated by temperature in our ferrimagnetic TbFeCo layer compared with Co or Fe. Once these two THz components are delicately set orthogonally, an elliptical THz wave is generated by the intrinsic phase difference at the THz frequency range. The feasible control of its polarization and chirality is demonstrated by three means: pump polarization, magnetic field, and temperature. These appealing observations may pave the way for the development of elliptical THz wave emitters and polarization-sensitive THz spectroscopy.

15.
Eur J Med Chem ; 269: 116337, 2024 Apr 05.
Article de Anglais | MEDLINE | ID: mdl-38537511

RÉSUMÉ

The global issue of antibiotic resistance is increasingly severe, highlighting the urgent necessity for the development of new antibiotics. Brevicidine, a natural cyclic lipopeptide, exhibits remarkable antimicrobial activity against Gram-negative bacteria. In this study, a comprehensive structure-activity relationship of Brevicidine was investigated through 20 newly synthesized cyclic lipopeptide analogs, resulting in the identification of an optimal linear analog 22. The sequence of analog 22 consisted of five d-amino acids and four non-natural amino acid 2,5-diaminovaleric acid (Orn) and conjugated with decanoic acid at N-terminal. Compared to Brevicidine, analog 22 was easier to synthesize, and exerted broad spectrum antimicrobial activity and excellent stability (t1/2 = 40.98 h). Additionally, analog 22 demonstrated a rapid bactericidal effect by permeating non-specifically through the bacterial membranes, thereby minimizing the likelihood of inducing resistance. Moreover, it exhibited remarkable efficacy in combating bacterial biofilms and reversing bacterial resistance to conventional antibiotics. Furthermore, it effectively suppressed the growth of bacteria in vital organs of mice infected with S. aureus ATCC 25923. In conclusion, analog 22 may represent a potential antimicrobial peptide for further optimization.


Sujet(s)
Peptides antimicrobiens , Staphylococcus aureus , Animaux , Souris , Antibactériens/pharmacologie , Antibactériens/composition chimique , Bactéries , Bactéries à Gram négatif , Lipopeptides/pharmacologie , Tests de sensibilité microbienne
16.
Eur J Med Chem ; 268: 116276, 2024 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-38452726

RÉSUMÉ

The emergence of bacterial resistance has posed a significant challenge to clinical antimicrobial treatment, rendering commonly used antibiotics ineffective. The development of novel antimicrobial agents and strategies is imperative for the treatment of resistant bacterial infections. Antimicrobial peptides (AMPs) are considered a promising class of antimicrobial agents due to their low propensity for resistance and broad-spectrum activity. Anoplin is a small linear α-helical natural antimicrobial peptide that was isolated from the venom of the solitary wasp Anplius samariensis. It exhibits rich biological activity, particularly broad-spectrum antimicrobial activity and low hemolytic activity. Over the past three decades, more than 40 research publications on anoplin have been made available online. This review focuses on the advancements of anoplin in antimicrobial research, encompassing its sources, characterization, antimicrobial activity, influencing factors and structural modifications. The aim is to provide assistances for the development of new antimicrobial agents that can combat bacterial resistance.


Sujet(s)
Anti-infectieux , Infections bactériennes , Humains , Peptides antimicrobiens cationiques/pharmacologie , Peptides antimicrobiens cationiques/composition chimique , Anti-infectieux/composition chimique , Venins de guêpe/composition chimique , Antibactériens/pharmacologie , Bactéries , Tests de sensibilité microbienne
17.
J Med Chem ; 67(8): 6365-6383, 2024 Apr 25.
Article de Anglais | MEDLINE | ID: mdl-38436574

RÉSUMÉ

Antimicrobial peptides (AMPs) have emerged as promising agents to combat the antibiotic resistance crisis due to their rapid bactericidal activity and low propensity for drug resistance. However, AMPs face challenges in terms of balancing enhanced antimicrobial efficacy with increased toxicity during modification processes. In this study, de novo d-type ß-hairpin AMPs are designed. The conformational transformation of self-assembling peptide W-4 in the environment of the bacterial membrane and the erythrocyte membrane affected its antibacterial activity and hemolytic activity and finally showed a high antibacterial effect and low toxicity. Furthermore, W-4 displays remarkable stability, minimal occurrence of drug resistance, and synergistic effects when combined with antibiotics. The in vivo studies confirm its high safety and potent wound-healing properties at the sites infected by bacteria. This study substantiates that nanostructured AMPs possess enhanced biocompatibility. These advances reveal the superiority of self-assembled AMPs and contribute to the development of nanoantibacterial materials.


Sujet(s)
Antibactériens , Peptides antimicrobiens , Hémolyse , Tests de sensibilité microbienne , Nanofibres , Tryptophane , Nanofibres/composition chimique , Tryptophane/composition chimique , Tryptophane/pharmacologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Antibactériens/synthèse chimique , Peptides antimicrobiens/composition chimique , Peptides antimicrobiens/pharmacologie , Peptides antimicrobiens/synthèse chimique , Hémolyse/effets des médicaments et des substances chimiques , Animaux , Humains , Souris
18.
Eur J Pharm Sci ; 195: 106723, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38336251

RÉSUMÉ

BACKGROUND AND OBJECTIVE: Neutrophil elastase has been identified as a potential therapeutic target for acute lung injury or acute respiratory distress syndrome, and Sivelestat is a selective, reversible and competitive neutrophil elastase inhibitor. This study was designed to investigate the safety, tolerability, pharmacokinetics and neutrophil elastase inhibitory effects of Sivelestat in healthy Chinese subjects. METHODS: A randomized, double-blind, placebo-controlled single- and multiple-dose escalation clinical trial was carried out. Briefly, healthy volunteers in twelve cohorts with 8 per cohort received 1.0-20.2 mg/kg/h Sivelestat or placebo in an intravenous infusion manner for two hours, and healthy volunteers in four cohorts received two hours intravenous infusion of 2.0-5.0 mg/kg/h Sivelestat or placebo with an interval of twelve hours for seven times. The safety and tolerability were evaluated and serial blood samples were collected for pharmacokinetics and neutrophil elastase inhibitory effects analysis at the specified time-point. RESULTS: A total of 128 subjects were enrolled and all participants completed the study except one. Sivelestat exhibited satisfactory safety and tolerability up to 20.2 mg/kg/h in single-dose cohorts and 5.0 mg/kg/h in multiple-dose cohorts. Even so, more attention should be paid to the safety risks when using high doses. The Cmax and AUC of Sivelestat increased in a dose dependent manner, and Tmax was similar for different dose cohorts. In multiple-dose cohorts, the plasma concentrations reached steady state 48 h after first administration and the accumulation of Cmax and AUC was not obvious. Furthermore, the Cmin_ss of 5.0 mg/kg/h dose cohort could meet the needs of clinical treatment. For some reason, the pharmacodynamics data revealed that the inhibitory effect of Sivelestat on neutrophil elastase content in healthy subjects was inconclusive. CONCLUSION: Sivelestat was safe and well tolerated with appropriate pharmacokinetic parameters, which provided support for more diverse dosing regimen in clinical application. CLINICAL TRIAL REGISTRATION: www.chinadrugtrials.org.cn identifier is CTR20210072.


Sujet(s)
Glycine/analogues et dérivés , Leukocyte elastase , Sulfonamides , Humains , Volontaires sains , Aire sous la courbe , Méthode en double aveugle , Chine , Relation dose-effet des médicaments
19.
Curr Biol ; 34(4): R135-R137, 2024 02 26.
Article de Anglais | MEDLINE | ID: mdl-38412820

RÉSUMÉ

Tea varieties exhibit seasonal theanine accumulation, with the high-theanine tea variety Rougui having a diverse root microbiota rich in nitrogen-related microbes. A synthetic community derived from Rougui roots enhances tea growth and theanine synthesis under nitrogen deficiency, emphasizing the microbiota's pivotal role.


Sujet(s)
Camellia sinensis , Camellia sinensis/métabolisme , Glutamates/métabolisme , Azote/métabolisme , Thé/métabolisme , Feuilles de plante/métabolisme
20.
Article de Anglais | MEDLINE | ID: mdl-38382917

RÉSUMÉ

INTRODUCTION: Our objective was to conduct a systematic review and meta-analysis of studies evaluating the oncological and reproductive outcomes of patients with endometrial atypical hyperplasia (AH) and endometrioid endometrial cancer (EEC) undergoing conservative therapy with hysteroscopic resection (HR). MATERIAL AND METHODS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for systematic reviews and meta-analyses. The study strictly followed the methodological framework proposed by the Cochrane Handbook and was retrospectively registered in PROSPERO (CRD42023469986). Searches were conducted in PubMed, Embase, and the Cochrane Library, from inception to October 10, 2023. A checklist based on items of the Newcastle-Ottawa Scale and the Methodological Index for Non-randomized Studies was used for quality assessment. The primary end points for this meta-analysis were complete response (CR), pregnancy, and live birth rates following HR-based therapy in patients with EEC or AH. The secondary end point was the recurrence rate (RR). RESULTS: Twenty-one articles involving 407 patients with clinical stage IA, low or intermediate grade, EEC, and 444 patients with AH managed with HR-based conservative treatment were included for this systematic review. CR to HR-based conservative therapy was achieved in 88.6% of patients with EEC and 97.0% of patients with AH. Of these, 30.6% and 24.2%, respectively, had live births. The overall pooled disease RR was 18.3% and 10.8% in patients with EEC and AH, respectively. Further subset analyses revealed that EEC patients with body mass index (BMI) ≤28 kg/m2 had higher CR rates as well as higher chances of pregnancy and live birth (91.6% CR, 32.9% pregnancy, 31.1% live birth) compared with patients with BMI >28 kg/m2 (86.4% CR, 28.4% pregnancy, 23.0% live birth). The HR followed by oral progestogen subgroup had higher CR rates and higher chances of pregnancy and live birth (91.8% CR, 36.3% pregnancy, 28.2% live birth) than the HR followed by the levonorgestrel intrauterine system subgroup (82.5% CR, 25.3% pregnancy, 16.3% live birth). CONCLUSIONS: Hysteroscopic resection followed by progestins appears to be a promising choice for fertility-sparing treatment in young patients with AH and EEC, with effective and safe responses. The live birth rate remains to be improved by providing medical guidance and encouragement.

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