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1.
Psychiatry Investig ; 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39219379

RÉSUMÉ

OBJECTIVE: This study aimed to investigate the impact of coronavirus disease-2019 (COVID-19) on suicide attempts and suicide deaths in South Korea, focusing on age and sex differences. METHODS: We analyzed the monthly number of suicide attempts and suicide deaths during pre-pandemic (January 2016-February 2020) and pandemic (March-December 2020) periods using nationally representative databases. We conducted an interrupted time series analysis and calculated the relative risk (RR) with a 95% confidence interval (CI), categorizing subjects into adolescents (<18), young adults (18-29), middle-aged (30-59), and older adults (≥60). RESULTS: During the pandemic, the number of suicide attempts abruptly declined in adolescents (RR [95% CI] level change: 0.58 [0.45-0.75]) and older adults (RR [95% CI] level change: 0.74 [0.66-0.84]). In older males, there was a significant rebound in the suicide attempt trend (RR [95% CI] slope change: 1.03 [1.01-1.05]). The number of suicide deaths did not change among age/sex strata significantly except for older males. There was a brief decline in suicide deaths in older males, while the trend showed a following increase with marginal significance (RR [95% CI] level change: 0.76 [0.66-0.88], slope change: 1.02 [1.00-1.04]). CONCLUSION: This study suggests the heterogeneous impact of the COVID-19 pandemic on suicide attempts and suicide deaths across age and sex strata in South Korea. These findings highlight the need for more targeted mental health interventions, given the observed trends in suicide attempts and suicide deaths during the pandemic.

2.
Carbohydr Polym ; 345: 122546, 2024 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-39227091

RÉSUMÉ

Herein, dexamethasone (DEX) nanocrystalline suspension (NS)-embedded hydrogel (NS-G) was constructed using a hydroxypropyl methylcellulose (HPMC) polymer to enhance cochlear delivery and attenuate hearing loss following intratympanic (IT) injection. Hydrophobic steroidal nanocrystals were prepared using a bead milling technique and incorporated into a polysaccharide hydrogel. The NS-G system with HPMC (average molecular weight, 86,000 g/mol; 15 mg/mL) was characterized as follows: rod-shaped drug crystalline; particle size <300 nm; and constant complex viscosity ≤1.17 Pa·s. Pulverization of the drug particles into submicron diameters enhanced drug dissolution, while the HPMC matrix increased the residence time in the middle ear cavity, exhibiting a controlled release profile. The IT NS-G system elicited markedly enhanced and prolonged drug delivery (> 9 h) to the cochlear tissue compared with that of DEX sodium phosphate (DEX-SP), a water-soluble prodrug. In mice with kanamycin- and furosemide-induced ototoxicity, NS-G markedly enhanced hearing preservation across all frequencies (8-32 kHz), as revealed by an auditory brainstem response test, compared with both saline and DEX-SP. Moreover, treatment with NS-G showed enhanced anti-inflammatory effects, as evidenced by decreased levels of inflammation-related cytokines. Therefore, the IT administration of DEX NS-loaded HPMC hydrogels is a promising strategy for treating hearing loss.


Sujet(s)
Cochlée , Dexaméthasone , Perte d'audition , Hydrogels , Dérivés de l'hypromellose , Injection intratympanique , Nanoparticules , Dexaméthasone/composition chimique , Dexaméthasone/administration et posologie , Animaux , Dérivés de l'hypromellose/composition chimique , Hydrogels/composition chimique , Nanoparticules/composition chimique , Souris , Cochlée/effets des médicaments et des substances chimiques , Cochlée/anatomopathologie , Perte d'audition/traitement médicamenteux , Perte d'audition/induit chimiquement , Libération de médicament , Mâle , Systèmes de délivrance de médicaments/méthodes
3.
Biochem Biophys Res Commun ; 738: 150544, 2024 Aug 13.
Article de Anglais | MEDLINE | ID: mdl-39163817

RÉSUMÉ

GLUT7 is a Class II glucose transporter predominantly expressed at the apical membrane of enterocytes in the small intestine. Here, we report the cryo-EM structure of nanodisc-reconstituted human GLUT7 in the apo state at 3.3 Å resolution. Our atomic model reveals a typical major facilitator superfamily fold, with the substrate-binding site open to the extracellular side of the membrane. Despite the nearly identical conformation to its closest family member, rat GLUT5, our structure unveils distinct features of the substrate-binding cavity that may influence substrate specificity and binding mode. A homology model of the inward-open human GLUT7 indicates that similar to other members of the GLUT family, it may undergo a global rocker-switch-like reorientation of the transmembrane bundles to facilitate substrate translocation across the membrane. Our work enhances the current structural understanding of the GLUT family, and lays a foundation for rational design of regulators of GLUTs and other sugar transporters.

4.
Life Sci Alliance ; 7(10)2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39089879

RÉSUMÉ

The large-conductance calcium-activated potassium (BKCa) channel, which is crucial for urinary bladder smooth muscle relaxation, is a potential target for overactive bladder treatment. Our prior work unveiled CTIBD as a promising BKCa channel activator, altering V 1/2 and G max This study investigates CTIBD's activation mechanism, revealing its independence from the Ca2+ and membrane voltage sensing of the BKCa channel. Cryo-electron microscopy disclosed that two CTIBD molecules bind to hydrophobic regions on the extracellular side of the lipid bilayer. Key residues (W22, W203, and F266) are important for CTIBD binding, and their replacement with alanine reduces CTIBD-mediated channel activation. The triple-mutant (W22A/W203A/F266A) channel showed the smallest V 1/2 shift with a minimal impact on activation and deactivation kinetics by CTIBD. At the single-channel level, CTIBD treatment was much less effective at increasing P o in the triple mutant, mainly because of a drastically increased dissociation rate compared with the WT. These findings highlight CTIBD's mechanism, offering crucial insights for developing small-molecule treatments for BKCa-related pathophysiological conditions.


Sujet(s)
Agonistes de canaux chlorure , Cryomicroscopie électronique , Canaux potassiques calcium-dépendants de grande conductance , Animaux , Humains , Sites de fixation , Calcium/métabolisme , Cellules HEK293 , Ouverture et fermeture des portes des canaux ioniques , Cinétique , Sous-unités alpha des canaux potassiques calcium-dépendants de grande conductance/agonistes , Sous-unités alpha des canaux potassiques calcium-dépendants de grande conductance/composition chimique , Sous-unités alpha des canaux potassiques calcium-dépendants de grande conductance/métabolisme , Canaux potassiques calcium-dépendants de grande conductance/agonistes , Canaux potassiques calcium-dépendants de grande conductance/composition chimique , Canaux potassiques calcium-dépendants de grande conductance/métabolisme , Double couche lipidique/métabolisme , Mutation , Liaison aux protéines , Agonistes de canaux chlorure/composition chimique , Agonistes de canaux chlorure/pharmacologie
5.
J Med Chem ; 67(16): 14443-14465, 2024 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-39102524

RÉSUMÉ

The P2X3 receptor (P2X3R), an ATP-gated cation channel predominantly expressed in C- and Aδ-primary afferent neurons, has been proposed as a drug target for neurological inflammatory diseases, e.g., neuropathic pain, and chronic cough. Aiming to develop novel, selective P2X3R antagonists, tetrazolopyrimidine-based hit compound 9 was optimized through structure-activity relationship studies by modifying the tetrazole core as well as side chain substituents. The optimized antagonist 26a, featuring a cyclopropane-substituted triazolopyrimidine core, displayed potent P2X3R-antagonistic activity (IC50 = 54.9 nM), 20-fold selectivity versus the heteromeric P2X2/3R, and high selectivity versus other P2XR subtypes. Noncompetitive P2X3R blockade was experimentally confirmed by calcium influx assays. Cryo-electron microscopy revealed that 26a stabilizes the P2X3R in its desensitized state, acting as a molecular barrier to prevent ions from accessing the central pore. In vivo studies in a rat neuropathic pain model (spinal nerve ligation) showed dose-dependent antiallodynic effects of 26a, thus presenting a novel, promising lead structure.


Sujet(s)
Cryomicroscopie électronique , Antagonistes des récepteurs purinergiques P2X , Pyrimidines , Récepteurs purinergiques P2X3 , Triazoles , Animaux , Antagonistes des récepteurs purinergiques P2X/pharmacologie , Antagonistes des récepteurs purinergiques P2X/composition chimique , Antagonistes des récepteurs purinergiques P2X/synthèse chimique , Relation structure-activité , Pyrimidines/pharmacologie , Pyrimidines/composition chimique , Pyrimidines/synthèse chimique , Rats , Récepteurs purinergiques P2X3/métabolisme , Humains , Triazoles/pharmacologie , Triazoles/composition chimique , Triazoles/synthèse chimique , Site allostérique , Mâle , Névralgie/traitement médicamenteux , Découverte de médicament , Rat Sprague-Dawley
6.
J Int Adv Otol ; 20(4): 372-374, 2024 Jul 29.
Article de Anglais | MEDLINE | ID: mdl-39162066

RÉSUMÉ

Hemangioma is a common vascular neoplasm that arises in the head and neck regions but is rare in the petrous bone. We report the first case of a solitary cavernous hemangioma in the mastoid antrum. A 68-year-old woman visited our hospital with a complaint of tinnitus without any other symptoms. Tinnitus of the right ear occurred especially when the patient yawned or swallowed. Both tympanic membranes appeared normal on otoscopic examination. On pure-tone audiometry, mild hearing loss up to 25 dB was detected in the right ear. Temporal bone computed tomography revealed a 7.0 mm × 4.5 mm × 5 mm, solitary soft tissue mass in the aditus ad antrum. Excisional biopsy was performed under general anesthesia through the canal wall as in a mastoidectomy. The mass was completely removed without any bleeding or ossicular chain damage. The mass was confirmed as a cavernous hemangioma. During follow-up, the patient's tinnitus and right low-tone hearing loss improved. No solitary hemangioma of the mastoid antrum has been reported previously. Surgical excision of the lesion appears to be proper treatment to achieve pathologic confirmation along with resolution of symptoms.


Sujet(s)
Hémangiome caverneux , Mastoïde , Acouphène , Humains , Femelle , Sujet âgé , Hémangiome caverneux/chirurgie , Hémangiome caverneux/anatomopathologie , Hémangiome caverneux/imagerie diagnostique , Hémangiome caverneux/diagnostic , Mastoïde/chirurgie , Mastoïde/anatomopathologie , Acouphène/étiologie , Mastoïdectomie/méthodes , Tomodensitométrie , Audiométrie tonale/méthodes , Tumeurs du crâne/chirurgie , Tumeurs du crâne/anatomopathologie , Tumeurs du crâne/diagnostic , Tumeurs du crâne/imagerie diagnostique , Résultat thérapeutique
7.
Nanoscale ; 16(35): 16313-16328, 2024 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-39110002

RÉSUMÉ

Carbon materials and their hybrid metal composites have garnered significant attention in biomedical applications due to their exceptional biocompatibility. This biocompatibility arises from their inherent chemical stability and low toxicity within biological systems. This review offers a comprehensive overview of carbon nanomaterials and their metal composites, emphasizing their biocompatibility-focused applications, including drug delivery, bioimaging, biosensing, and tissue engineering. The paper outlines advancements in surface modifications, coatings, and functionalization techniques designed to enhance the biocompatibility of carbon materials, ensuring minimal adverse effects in biological systems. A comprehensive investigation into hybrid composites integrating carbon nanomaterials is conducted, categorizing them as fullerenes, carbon quantum dots, carbon nanotubes, carbon nanofibers, graphene, and diamond-like carbon. The concluding section addresses regulatory considerations and challenges associated with integrating carbon materials into medical devices. This review culminates by providing insights into current achievements, challenges, and future directions, underscoring the pivotal role of carbon nanomaterials and their metal composites in advancing biocompatible applications.


Sujet(s)
Matériaux biocompatibles , Carbone , Humains , Matériaux biocompatibles/composition chimique , Carbone/composition chimique , Ingénierie tissulaire , Métaux/composition chimique , Techniques de biocapteur , Nanotubes de carbone/composition chimique , Graphite/composition chimique , Animaux , Systèmes de délivrance de médicaments
8.
Nat Immunol ; 2024 Aug 23.
Article de Anglais | MEDLINE | ID: mdl-39179931

RÉSUMÉ

The drivers of immune evasion are not entirely clear, limiting the success of cancer immunotherapies. Here we applied single-cell spatial and perturbational transcriptomics to delineate immune evasion in high-grade serous tubo-ovarian cancer. To this end, we first mapped the spatial organization of high-grade serous tubo-ovarian cancer by profiling more than 2.5 million cells in situ in 130 tumors from 94 patients. This revealed a malignant cell state that reflects tumor genetics and is predictive of T cell and natural killer cell infiltration levels and response to immune checkpoint blockade. We then performed Perturb-seq screens and identified genetic perturbations-including knockout of PTPN1 and ACTR8-that trigger this malignant cell state. Finally, we show that these perturbations, as well as a PTPN1/PTPN2 inhibitor, sensitize ovarian cancer cells to T cell and natural killer cell cytotoxicity, as predicted. This study thus identifies ways to study and target immune evasion by linking genetic variation, cell-state regulators and spatial biology.

9.
Appl Microbiol Biotechnol ; 108(1): 403, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38954014

RÉSUMÉ

2-Keto-3-deoxy-galactonate (KDGal) serves as a pivotal metabolic intermediate within both the fungal D-galacturonate pathway, which is integral to pectin catabolism, and the bacterial DeLey-Doudoroff pathway for D-galactose catabolism. The presence of KDGal enantiomers, L-KDGal and D-KDGal, varies across these pathways. Fungal pathways generate L-KDGal through the reduction and dehydration of D-galacturonate, whereas bacterial pathways produce D-KDGal through the oxidation and dehydration of D-galactose. Two distinct catabolic routes further metabolize KDGal: a nonphosphorolytic pathway that employs aldolase and a phosphorolytic pathway involving kinase and aldolase. Recent findings have revealed that L-KDGal, identified in the bacterial catabolism of 3,6-anhydro-L-galactose, a major component of red seaweeds, is also catabolized by Escherichia coli, which is traditionally known to be catabolized by specific fungal species, such as Trichoderma reesei. Furthermore, the potential industrial applications of KDGal and its derivatives, such as pyruvate and D- and L-glyceraldehyde, are underscored by their significant biological functions. This review comprehensively outlines the catabolism of L-KDGal and D-KDGal across different biological systems, highlights stereospecific methods for discriminating between enantiomers, and explores industrial application prospects for producing KDGal enantiomers. KEY POINTS: • KDGal is a metabolic intermediate in fungal and bacterial pathways • Stereospecific enzymes can be used to identify the enantiomeric nature of KDGal • KDGal can be used to induce pectin catabolism or produce functional materials.


Sujet(s)
Voies et réseaux métaboliques , Oses acides , Oses acides/métabolisme , Galactose/métabolisme , Galactose/analogues et dérivés , Champignons/métabolisme , Champignons/enzymologie , Bactéries/métabolisme , Bactéries/enzymologie , Escherichia coli/métabolisme , Escherichia coli/génétique , Stéréoisomérie
10.
Nanomaterials (Basel) ; 14(11)2024 May 27.
Article de Anglais | MEDLINE | ID: mdl-38869565

RÉSUMÉ

Background. The aim of the study was to synthesize liposomal nanoparticles loaded with temozolomide and ferucarbotran (LTF) and to evaluate the theranostic effect of LTF in the glioma model. Methods. We synthesized an LTF that could pass through the Blood Brain Barrier (BBB) and localize in brain tumor tissue with the help of magnet guidance. We examined the chemical characteristics. Cellular uptake and cytotoxicity studies were conducted in vitro. A biodistribution and tumor inhibition study was conduted using an in vivo glioma model. Results. The particle size and surface charge of LTF show 108 nm and -38 mV, respectively. Additionally, the presence of ferucarbotran significantly increased the contrast agent effect of glioma compared to the control group in MR imaging. Magnet-guided LTF significantly reduced the tumor size compared to control and other groups. Furthermore, compared to the control group, our results demonstrate a significant inhibition in brain tumor size and an increase in lifespan. Conclusions. These findings suggest that the LTF with magnetic guidance represents a novel approach to address current obstacles, such as BBB penetration of nanoparticles and drug resistance. Magnet-guided LTF is able to enhance therapeutic efficacy in mouse brain glioma.

11.
Small ; : e2403253, 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38860540

RÉSUMÉ

The electrochemical nitrate reduction reaction (NO3RR) is of significance in regards of environmentally friendly issues and green ammonia production. However, relatively low performance with a competitive hydrogen evolution reaction (HER) is a challenge to overcome for the NO3RR. In this study, oxygen vacancy-controlled copper oxide (CuOx) catalysts through a plasma treatment are successfully prepared and supported on high surface area porous carbon that are co-doped with N, Se species for its enhanced electrochemical properties. The oxygen vacancy-increased CuOx catalyst supported on the N,Se co-doped porous carbon (CuOx-H/NSePC) exhibited the highest NO3RR performance with faradaic efficiency (FE) of 87.2% and yield of 7.9 mg cm-2 h-1 for the ammonia production, representing significant enhancements of FE and ammonia yield as compared to the un-doped or the oxygen vacancy-decreased catalysts. This high performance should be attributed to a significant increase in the catalytic active sites with facilitated energetics from strategies of doping the catalytic materials and weakening the N─O bonding strength for the adsorption of NO3 - ions on the modulated oxygen vacancies. This results show a promise that co-doping of heteroatoms and regulating of oxygen vacancies can be key factors for performance enhancement, suggesting new guidelines for effective catalyst design of NO3RR.

12.
Int J Biol Macromol ; 274(Pt 2): 133268, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38944083

RÉSUMÉ

p-Hydroxybenzoate hydroxylase (PHBH) catalyzes the ortho-hydroxylation of 4-hydroxybenzoate (4-HB) to protocatechuate (PCA). PHBHs are commonly known as homodimers, and the prediction of pyridine nucleotide binding and specificity remains an ongoing focus in this field. Therefore, our study aimed to determine the dimerization interface in AspPHBH from Arthrobacter sp. PAMC25564 and identify the canonical pyridine nucleotide-binding residues, along with coenzyme specificity, through site-directed mutagenesis. The results confirm a functional dimeric assembly from a tetramer that appeared in the crystallographic asymmetric unit identical to that established in previous studies. Furthermore, AspPHBH exhibits coenzyme versatility, utilizing both NADH and NADPH, with a preference for NADH. Rational engineering experiments demonstrated that targeted mutations in coenzyme surrounding residues profoundly impact NADPH binding, leading to nearly abrogated enzymatic activity compared to that of NADH. R50, R273, and S166 emerged as significant residues for NAD(P)H binding, having a near-fatal impact on NADPH binding compared to NADH. Likewise, the E44 residue plays a critical role in determining coenzyme specificity. Overall, our findings contribute to the fundamental understanding of the determinants of PHBH's active dimeric conformation, coenzyme binding and specificity holding promise for biotechnological advancements.


Sujet(s)
4-Hydroxybenzoate 3-monooxygenase , Arthrobacter , Multimérisation de protéines , Arthrobacter/enzymologie , 4-Hydroxybenzoate 3-monooxygenase/métabolisme , 4-Hydroxybenzoate 3-monooxygenase/composition chimique , NADP/métabolisme , Modèles moléculaires , Coenzymes/métabolisme , Spécificité du substrat , NAD/métabolisme , Conformation des protéines , Mutagenèse dirigée , Liaison aux protéines , Sites de fixation , Protéines bactériennes/composition chimique , Protéines bactériennes/métabolisme , Protéines bactériennes/génétique , Parabènes
13.
Int J Food Microbiol ; 419: 110749, 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-38788343

RÉSUMÉ

This study investigated the synergistic effects of ammonium persulfate (PS) and ultrasound (US) on the inactivation of Escherichia coli O157:H7 in buffered peptone water (BPW) and orange juice products. A comprehensive assessment of PS concentrations ranging from 1 to 300 mM, considering not only the statistical significance but also the reliability and stability of the experimental outcomes, showed that 150 mM was the optimal PS concentration for the inactivation of E. coli O157:H7. Additionally, US output intensities varying from 30 % to 60 % of the maximum US intensity were evaluated, and 50 % US amplitude was found to be the optimal US condition. A 50 % amplitude setting on the sonicator corresponds to half of its maximum displacement, approximately 60 µm, based on a maximum amplitude of 120 µm. The inactivation level of E. coli O157:H7 was significantly enhanced by the combined treatment of PS and US, compared to each treatment of PS and US alone. In the BPW, a 10-min treatment with the combination of PS and US resulted in a significant synergistic inactivation, achieving up to a log reduction of 3.86 log CFU/mL. Similarly, in orange juice products, a 5-min treatment with the combination of PS and US yielded a significant synergistic inactivation, with a reduction reaching 5.90 log CFU/mL. Although the treatment caused a significant color change in the sample, the visual differences between the treated and non-treated groups were not pronounced. Furthermore, the combined treatment in orange juice demonstrated significantly enhanced antimicrobial efficacy relative to BPW. Despite identical 5-min treatment periods, the application in orange juice resulted in a substantially higher log reduction of E. coli O157:H7, achieving 7.16 log CFU/mL at a reduced PS concentration of 30 mM, whereas the same treatment in BPW yielded only a 2.89 log CFU/mL reduction at a PS concentration of 150 mM, thereby highlighting its significantly superior antimicrobial performance in orange juice. The mechanism underlying microbial inactivation, induced by the combined treatment of PS and US, was identified as significant cell membrane damage. This damage is mediated by sulfate radicals, generated through the sono-activation of persulfate. In addition, the low pH of orange juice, measured at 3.7, is likely to have further deteriorated the E. coli O157:H7 cells compared to BPW (pH 7.2), by disrupting their cell membranes, proton gradients, and energy metabolism. These findings underscore the effectiveness of PS and US integration as a promising approach for non-thermal pasteurization in the food industry. Further research is needed to optimize treatment parameters and fully explore the practical application of this technique in large-scale food processing operations. Sensory evaluation and nutritional assessment are also necessary to address the limitations of PS.


Sujet(s)
Sulfate d'ammonium , Citrus sinensis , Numération de colonies microbiennes , Escherichia coli O157 , Jus de fruits et de légumes , Escherichia coli O157/effets des médicaments et des substances chimiques , Escherichia coli O157/croissance et développement , Jus de fruits et de légumes/microbiologie , Citrus sinensis/composition chimique , Sulfate d'ammonium/pharmacologie , Sulfate d'ammonium/composition chimique , Peptones/pharmacologie , Peptones/composition chimique , Microbiologie alimentaire , Viabilité microbienne/effets des médicaments et des substances chimiques , Eau/composition chimique , Eau/pharmacologie
14.
Commun Biol ; 7(1): 672, 2024 May 31.
Article de Anglais | MEDLINE | ID: mdl-38822018

RÉSUMÉ

ATP-binding cassette transporter B6 (ABCB6), a protein essential for heme biosynthesis in mitochondria, also functions as a heavy metal efflux pump. Here, we present cryo-electron microscopy structures of human ABCB6 bound to a cadmium Cd(II) ion in the presence of antioxidant thiol peptides glutathione (GSH) and phytochelatin 2 (PC2) at resolutions of 3.2 and 3.1 Å, respectively. The overall folding of the two structures resembles the inward-facing apo state but with less separation between the two halves of the transporter. Two GSH molecules are symmetrically bound to the Cd(II) ion in a bent conformation, with the central cysteine protruding towards the metal. The N-terminal glutamate and C-terminal glycine of GSH do not directly interact with Cd(II) but contribute to neutralizing positive charges of the binding cavity by forming hydrogen bonds and van der Waals interactions with nearby residues. In the presence of PC2, Cd(II) binding to ABCB6 is similar to that observed with GSH, except that two cysteine residues of each PC2 molecule participate in Cd(II) coordination to form a tetrathiolate. Structural comparison of human ABCB6 and its homologous Atm-type transporters indicate that their distinct substrate specificity might be attributed to variations in the capping residues situated at the top of the substrate-binding cavity.


Sujet(s)
Transporteurs ABC , Humains , Transporteurs ABC/composition chimique , Transporteurs ABC/métabolisme , Transporteurs ABC/ultrastructure , Sites de fixation , Cadmium/métabolisme , Cadmium/composition chimique , Cryomicroscopie électronique , Glutathion/métabolisme , Glutathion/composition chimique , Modèles moléculaires , Phytochélatines/métabolisme , Phytochélatines/composition chimique , Liaison aux protéines , Conformation des protéines
15.
Biomolecules ; 14(5)2024 Apr 23.
Article de Anglais | MEDLINE | ID: mdl-38785916

RÉSUMÉ

Tumor necrosis factor receptor-associated factor (TRAF) proteins play pivotal roles in a multitude of cellular signaling pathways, encompassing immune response, cell fate determination, development, and thrombosis. Their involvement in these processes hinges largely on their ability to interact directly with diverse receptors via the TRAF domain. Given the limited binding interface, understanding how specific TRAF domains engage with various receptors and how structurally similar binding interfaces of TRAF family members adapt their distinct binding partners has been the subject of extensive structural investigations over several decades. This review presents an in-depth exploration of the current insights into the structural and molecular diversity exhibited by the TRAF domain and TRAF-binding motifs across a range of receptors, with a specific focus on TRAF1.


Sujet(s)
Facteur-1 associé aux récepteurs de TNF , Humains , Facteur-1 associé aux récepteurs de TNF/métabolisme , Facteur-1 associé aux récepteurs de TNF/composition chimique , Facteur-1 associé aux récepteurs de TNF/génétique , Animaux , Liaison aux protéines , Transduction du signal , Domaines protéiques , Modèles moléculaires
16.
Methods Enzymol ; 694: 137-165, 2024.
Article de Anglais | MEDLINE | ID: mdl-38492949

RÉSUMÉ

This chapter explores advanced single-molecule techniques for studying protein-DNA interactions, particularly focusing on Replication Protein A (RPA) using a force-fluorescence setup. It combines magnetic tweezers (MT) with total internal reflection fluorescence (TIRF) microscopy, enabling detailed observation of DNA behavior under mechanical stress. The chapter details the use of DNA hairpins and bare DNA to examine RPA's binding dynamics and its influence on DNA's mechanical properties. This approach provides deeper insights into RPA's role in DNA replication, repair, and recombination, highlighting its significance in maintaining genomic stability.


Sujet(s)
ADN simple brin , ADN , Fluorescence , Réplication de l'ADN , Protéines de liaison à l'ADN/métabolisme
17.
J Am Chem Soc ; 146(7): 4393-4401, 2024 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-38329893

RÉSUMÉ

For the construction of hierarchical superstructures with biaxial anisotropic absorption, a newly synthesized diacetylene-functionalized bipyridinium is self-assembled to use an electron-accepting host for capturing and arranging guests. The formation of the donor-acceptor complex triggers an intermolecular charge transfer, leading to chromophore activation. Polarization-dependent multichroic thin films are prepared through a sequential process of single-coating, self-assembly, and topochemical polymerization of host-guest chromophores. Molecular packing structures constructed in the single-layer optical thin film possess orthogonal absorption axes for two different wavelengths. By tuning the linear polarization angle, the color of the optical thin film can be intentionally controlled. This single-layered multichroic film provides a new pathway for the development of anticounterfeiting and multiplexing encryptions.

18.
Nutr Res Pract ; 18(1): 149-164, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38352210

RÉSUMÉ

BACKGROUND/OBJECTIVES: The economic recession caused by the coronavirus disease 2019 pandemic disproportionately affected poor and vulnerable populations globally. Better uunderstanding of vulnerability to shocks in food supply and demand in the Asia Pacific region is needed. SUBJECTS/METHODS: Using secondary data from rapid assessment surveys during the pandemic response (n = 10,420 in mid-2020; n = 6,004 in mid-2021) in India, Indonesia, Myanmar, and Vietnam, this study examined the risk factors for reported income reduction or job loss in mid-2021 and the temporal trend in food security status (household food availability, and market availability and affordability of essential items) from mid-2020 to mid-2021. RESULTS: The proportion of job loss/reduced household income was highest in India (60.4%) and lowest in Indonesia (39.0%). Urban residence (odds ratio [OR] range, 2.20-4.11; countries with significant results only), female respondents (OR range, 1.40-1.69), engagement in daily waged labor (OR range, 1.54-1.68), and running a small trade/business (OR range, 1.66-2.71) were significantly associated with income reduction or job loss in three out of 4 countries (all P < 0.05). Food stock availability increased significantly in 2021 compared to 2020 in all four countries (OR range, 1.91-4.45) (all P < 0.05). Availability of all essential items at markets increased in India (OR range, 1.45-3.99) but decreased for basic foods, hygiene items, and medicine in Vietnam (OR range, 0.81-0.86) in 2021 compared to 2020 (all P < 0.05). In 2021, the affordability of all essential items significantly improved in India (OR range, 1.18-3.49) while the affordability of rent, health care, and loans deteriorated in Indonesia (OR range, 0.23-0.71) when compared to 2020 (all P < 0.05). CONCLUSIONS: Long-term social protection programs need to be carefully designed and implemented to address food insecurity among vulnerable groups, considering each country's market conditions, consumer food purchasing behaviors, and financial support capacity.

19.
Am J Trop Med Hyg ; 110(2): 270-273, 2024 02 07.
Article de Anglais | MEDLINE | ID: mdl-38190753

RÉSUMÉ

Cryptococcus neoformans infections occur most frequently in immunocompromised patients. Here, we report a case of cryptococcal meningitis in a previously immunocompetent 78-year-old female patient after treatment of COVID-19. Underlying diseases included hypertension, hyperlipidemia, and diabetes. The patient was critically ill and was treated with remdesivir, baricitinib, and dexamethasone. During hospitalization, her mental state changed, and C. neoformans was detected in the cerebrospinal fluid. She died despite receiving antifungal treatment. Treatment of COVID-19 may be a predisposing factor for C. neoformans infection. There is a need for concern and countermeasures for opportunistic fungal infections that may accompany COVID-19.


Sujet(s)
COVID-19 , Cryptococcus neoformans , Méningite cryptococcique , Humains , Femelle , Sujet âgé , Méningite cryptococcique/diagnostic , Méningite cryptococcique/traitement médicamenteux , Antifongiques/usage thérapeutique
20.
BMC Infect Dis ; 24(1): 3, 2024 Jan 02.
Article de Anglais | MEDLINE | ID: mdl-38166787

RÉSUMÉ

BACKGROUNDS: Remdesivir (RDV) is an antiviral agent approved for the treatment of coronavirus disease 2019 (COVID-19); however, is not recommended for patients with renal impairment. Due to limitations associated with prospective clinical trials, real-world data on the safety and efficacy of RDV in patients with renal impairment are necessary. METHODS: Propensity score-matched (PSM) retrospective analysis was conducted between March 2020 and September 2022 in COVID-19 patients with an eGFR < 30 mL/min in four Korean hospitals. The RDV treatment group was matched to the untreated control group. The safety and clinical outcomes in patients who received RDV were analyzed. RESULTS: A total of 564 patients were enrolled; 229 patients received RDV either for treatment or prophylaxis. On day 5, no difference in nephrotoxicity was observed between the two groups, and liver enzyme levels were within the normal range. In multivariate analysis for new dialysis, RDV treatment was not a risk factor for new dialysis. Among the 564 patients, 417 were indicated for a 5-day course of RDV treatment and 211 patients were treated with RDV. After PSM, no differences in the clinical outcomes were observed between the two groups. CONCLUSION: RDV use in COVID-19 patients with renal impairment did not result in significant nephrotoxicity or hepatotoxicity.


Sujet(s)
COVID-19 , Insuffisance rénale , Humains , Traitements médicamenteux de la COVID-19 , Score de propension , Études prospectives , Études rétrospectives , Insuffisance rénale/complications , Antiviraux/effets indésirables
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