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1.
Int Immunopharmacol ; 142(Pt B): 113207, 2024 Sep 22.
Article de Anglais | MEDLINE | ID: mdl-39312860

RÉSUMÉ

Surgical resection is the best-known approach for breast cancer treatment. However, post-operative metastases increase the rate of death. The potential effect of anesthetic drugs on long-term tumor growth, risk of metastasis, and recurrence after surgery has been investigated in cancer patients. However, the underlying mechanisms remain unclear. Therefore, we aimed to elucidate the anti-metastatic effect of lidocaine combined with common anesthetics and its mechanisms of action on lung metastasis in breast cancer models. The combination of lidocaine with propofol or sevoflurane inhibited the growth of TNBC cells compared to treatment alone. In addition, the combination effectively inhibited cancer cell migration and invasion. It suppressed tumor growth and increased the survival rate in breast 4 T1 orthotopic models. More importantly, it inhibited lung metastasis and recurrence compared with groups treated with a single anesthetic. In co-culture with TAMs and TNBC cells, lidocaine not only reduced M2-tumor-associated macrophages (TAM) that were increased by sevoflurane or propofol but also increased M1 macrophage polarization, impeding tumor growth in TNBC. Also, we found that the transforming growth factor-ß (TGF-ß) derived from TAMs increased EMT signaling in TNBC cells, and that lidocaine affected cancer cells as well as M2-TAMs, inducing M2 to M1 reprogramming and decreasing TGF-ß/Smads-mediated EMT signaling in TNBC cells, leading to inhibition of cancer metastasis and recurrence. These findings suggest lidocaine combined with general anesthetics as a potential therapeutic approach for the inhibition of recurrence and metastasis of breast cancer patients undergoing curative resection.

2.
Open Biol ; 14(9): 240141, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39317333

RÉSUMÉ

Gregarines are a large and diverse subgroup of Apicomplexa, a lineage of obligate animal symbionts including pathogens such as Plasmodium, the malaria parasite. Unlike Plasmodium, however, gregarines are poorly studied, despite the fact that as early-branching apicomplexans they are crucial to our understanding of the origin and evolution of all apicomplexans and their parasitic lifestyle. Exemplifying this, the earliest branch of gregarines, the archigregarines, are particularly poorly studied: around 80 species have been described from marine invertebrates, but almost all of them were assigned to a single genus, Selenidium. Most are known only from light micrographs and largely unresolved rDNA phylogenies, where they exhibit a great deal of sequence variation, and fall into four subclades. To resolve the relationships within archigregarines, we sequenced 12 single-cell transcriptomes from species representing all four known subclades, as well as one blastogregarine (which frequently branch with Selenidium). A 190-gene phylogenomic tree confirmed four maximally supported individual clades of archigregarines and blastogregarines. These clades are discrete and distantly related, and also correlate with host identity. We propose the establishment of three novel genera of archigregarines to reflect their phylogenetic diversity and host range, and nine novel species isolated from a range of marine invertebrates.


Sujet(s)
Apicomplexa , Phylogenèse , Apicomplexa/génétique , Apicomplexa/classification , Animaux , Transcriptome , Variation génétique
3.
J Eukaryot Microbiol ; : e13053, 2024 Aug 08.
Article de Anglais | MEDLINE | ID: mdl-39117563

RÉSUMÉ

Gregarine apicomplexans are ubiquitous endosymbionts of invertebrate hosts. Despite their ecological and evolutionary importance, inferences about the phylogenetic relationships of major gregarine groups, such as the Lecudinidae and Urosporidae, have been hindered by vague taxonomic definitions and limited molecular and morphological data. In this study, we investigated five gregarine species collected from four families of polychaete hosts (Nereididae, Oenonidae, Hesionidae, and Phyllodocidae) using light microscopy (LM) and scanning electron microscopy (SEM). We also generated small subunit ribosomal DNA sequences from these species and conducted molecular phylogenetic analyses to elucidate the evolutionary relationships within the Lecudinoidea. Our results include new molecular and morphological data for two previously described species (Lecudina cf. platynereidis and Lecudina cf. arabellae), the discovery of a new species of Lecudina (L. oxydromus n. sp.), and the discovery of two novel species, namely Amplectina cordis n. gen. et. n. sp. and Sphinctocystis inclina n. sp. These two species exhibited unique shapes and movements, resembling those of urosporids but with a phylogenetic affinity to lecudinids, blurring the border between lecudinids and urosporids. Our study emphasizes the need for further investigations into this highly diverse group, which has achieved great success across multiple animal phyla with diverse shapes and movements.

4.
J Chem Phys ; 160(22)2024 Jun 14.
Article de Anglais | MEDLINE | ID: mdl-38856063

RÉSUMÉ

We performed high-level ab initio quantum chemical calculations, incorporating higher-order excitations, spin-orbit coupling (SOC), and the Gaunt interaction, to calculate the electron affinities (EAs) of alkaline earth (AE) metal atoms (Ca, Sr, Ba, and Ra), which are notably small. The coupled-cluster singles and doubles with perturbative triples [CCSD(T)] method is insufficient to accurately calculate the EAs of AE metal atoms. Higher-order excitations proved crucial, with the coupled-cluster singles, doubles, and triples with perturbative quadruples [CCSDT(2)Q] method effectively capturing dynamic electron correlation effects. The contributions of SOC (ΔESOs) to the EAs calculated using the multireference configuration interaction method with the Davidson correction, including SOC, positively enhance the EAs; however, these contributions are overestimated. The Dirac-Hartree-Fock (DHF)-CCSD(T) method addresses this overestimation and provides reasonable values for ΔESO (ΔESO-D). Employing additional sets of diffuse and core-valence correlation basis sets is critical for accurately calculating the EAs of AE metal atoms. The contributions of the Gaunt interaction (ΔEGaunt) to the EAs of AE metal atoms are negligible. Notably, the CCSDT(2)Q with the complete basis set limit + ΔESO-D + ΔEGaunt produced EA values for Ca, Sr, and Ba that closely aligned with experimental data and achieved accuracy exceeding the chemical accuracy. Based on our findings, the accurately proposed EA for Ra is 9.88 kJ/mol.

5.
Microorganisms ; 12(5)2024 Apr 27.
Article de Anglais | MEDLINE | ID: mdl-38792706

RÉSUMÉ

Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics.

6.
Parasitology ; 151(4): 400-411, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38465385

RÉSUMÉ

Individual organisms can host multiple species of parasites (or symbionts), and one species of parasite can infect different host species, creating complex interactions among multiple hosts and parasites. When multiple parasite species coexist in a host, they may compete or use strategies, such as spatial niche partitioning, to reduce competition. Here, we present a host­symbiont system with two species of Selenidium (Apicomplexa, Gregarinida) and one species of astome ciliate co-infecting two different species of slime feather duster worms (Annelida, Sabellidae, Myxicola) living in neighbouring habitats. We examined the morphology of the endosymbionts with light and scanning electron microscopy (SEM) and inferred their phylogenetic interrelationships using small subunit (SSU) rDNA sequences. In the host 'Myxicola sp. Quadra', we found two distinct species of Selenidium; S. cf. mesnili exclusively inhabited the foregut, and S. elongatum n. sp. inhabited the mid to hindgut, reflecting spatial niche partitioning. Selenidium elongatum n. sp. was also present in the host M. aesthetica, which harboured the astome ciliate Pennarella elegantia n. gen. et sp. Selenidium cf. mesnili and P. elegantia n. gen. et sp. were absent in the other host species, indicating host specificity. This system offers an intriguing opportunity to explore diverse aspects of host­endosymbiont interactions and competition among endosymbionts.


Sujet(s)
Apicomplexa , Spécificité d'hôte , Phylogenèse , Symbiose , Animaux , Apicomplexa/physiologie , Apicomplexa/génétique , Apicomplexa/classification , Apicomplexa/ultrastructure , Co-infection/parasitologie , Co-infection/médecine vétérinaire , Ciliophora/physiologie , Ciliophora/classification , Ciliophora/génétique , Annelida , Interactions hôte-parasite , Microscopie électronique à balayage , Maladies des oiseaux/parasitologie
7.
Dermatol Surg ; 50(4): 360-365, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38318968

RÉSUMÉ

BACKGROUND: Using a thread for wound closure promotes healing and minimizes contamination by foreign substances. Threads have also been employed in esthetic surgery; however, functional threads that can improve wrinkles and rejuvenate the skin are required. OBJECTIVE: To evaluate the suitability of polydioxanone threads coated with polyethylene glycol, hyaluronic acid, and amino acids for use in the medical field because such formulations are expected to promote regeneration and collagen synthesis. MATERIALS AND METHODS: Physical properties (diameter [ n = 20], tensile strength [ n = 20], strength retention rate [ n = 10], and scanning electron microscopy images) and cytotoxicity (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays) of polydioxanone threads coated with polyethylene glycol, hyaluronic acid, and amino acids were assessed and compared with those of uncoated polydioxanone threads. Analyses were performed using IBM SPSS Statistics (Statistical significance; p values <.05). RESULTS: The size standards for tensile strength (≥63.5 N) and diameter (average 0.570-0.610 mm) were met. There were no differences in the physical properties of the coated and uncoated threads; however, the biocompatibility of coated threads was high owing to low cytotoxicity. CONCLUSION: Threads coated with materials that can promote regeneration are suitable for use in the medical field.


Sujet(s)
Polydioxanone , Rhytidoplastie , Humains , Acide hyaluronique , Rhytidoplastie/méthodes , Acides aminés , Polyéthylène glycols , Matériaux de suture
8.
J Cosmet Dermatol ; 23(6): 2240-2248, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38375987

RÉSUMÉ

BACKGROUND: To increase skin permeability, various transdermal delivery techniques have been developed. However, due to the stratum corneum as a skin barrier, transdermal delivery remains limited. AIMS: In this study, we evaluated efficacy and safety of arc-poration as a novel technique disrupting the stratum corneum. RESULTS: Optical images and histological analysis using reconstituted human skin and porcine skin showed that the treatment of arc-poration created micropores with an average diameter of approximately 100 µm only to the depth of the stratum corneum, but not viable epidermis. In addition, the Franz diffusion cell experiment using reconstituted human skin showed a remarkable increase in permeability following pretreatment with arc-poration. Clinical results clearly demonstrated the enhancement of the skin-improving effect of cosmetics by pretreatment of arc-poration in terms of gloss, hydration, flakiness, texture, tone, tone evenness, and pigmentation of skin, without causing abnormal skin responses. The concentration of ozone and nitrogen oxides generated by arc-poration was below the permissible value for the human body. CONCLUSIONS: Arc-poration can increase skin permeability by creating stratum corneum-specific micropores, which can enhance the skin-improving effect of cosmetics without adverse responses.


Sujet(s)
Administration par voie cutanée , Perméabilité , Absorption cutanée , Humains , Suidae , Absorption cutanée/effets des médicaments et des substances chimiques , Animaux , Adulte , Femelle , Peau/métabolisme , Peau/effets des médicaments et des substances chimiques , Épiderme/métabolisme , Épiderme/effets des médicaments et des substances chimiques , Cosmétiques/administration et posologie , Cosmétiques/pharmacocinétique , Cosmétiques/composition chimique , Jeune adulte
9.
Exp Mol Med ; 56(2): 478-490, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38413821

RÉSUMÉ

Idiopathic pulmonary fibrosis (IPF) is characterized by aberrant lung remodeling and the excessive accumulation of extracellular matrix (ECM) proteins. In a previous study, we found that the levels of ornithine aminotransferase (OAT), a principal enzyme in the proline metabolism pathway, were increased in the lungs of patients with IPF. However, the precise role played by OAT in the pathogenesis of IPF is not yet clear. The mechanism by which OAT affects fibrogenesis was assessed in vitro using OAT-overexpressing and OAT-knockdown lung fibroblasts. The therapeutic effects of OAT inhibition were assessed in the lungs of bleomycin-treated mice. OAT expression was increased in fibrotic areas, principally in interstitial fibroblasts, of lungs affected by IPF. OAT levels in the bronchoalveolar lavage fluid of IPF patients were inversely correlated with lung function. The survival rate was significantly lower in the group with an OAT level >75.659 ng/mL than in the group with an OAT level ≤75.659 ng/mL (HR, 29.53; p = 0.0008). OAT overexpression and knockdown increased and decreased ECM component production by lung fibroblasts, respectively. OAT knockdown also inhibited transforming growth factor-ß1 (TGF)-ß1 activity and TGF-ß1 pathway signaling. OAT overexpression increased the generation of mitochondrial reactive oxygen species (ROS) by activating proline dehydrogenase. The OAT inhibitor L-canaline significantly attenuated bleomycin-induced lung injury and fibrosis. In conclusion, increased OAT levels in lungs affected by IPF contribute to the progression of fibrosis by promoting excessive mitochondrial ROS production, which in turn activates TGF-ß1 signaling. OAT may be a useful target for treating patients with fibrotic lung diseases, including IPF.


Sujet(s)
Fibrose pulmonaire idiopathique , Facteur de croissance transformant bêta-1 , Animaux , Humains , Souris , Bléomycine , Protéines de la matrice extracellulaire , Fibrose , Poumon/enzymologie , Ornithine-oxo-acid transaminase , Espèces réactives de l'oxygène
10.
Pharmaceutics ; 16(1)2024 Jan 13.
Article de Anglais | MEDLINE | ID: mdl-38258116

RÉSUMÉ

A liver injury was recently reported for saxagliptin, which is a dipeptidyl peptidase-4 (DPP-4) inhibitor. However, the underlying mechanisms of saxagliptin-induced liver injury remain unknown. This study aimed to evaluate whether saxagliptin, a potent and selective DPP-4 inhibitor that is globally used for treating type 2 diabetes mellitus, binds to the nucleophiles in vitro. Four DPP-4 inhibitors, including vildagliptin, were evaluated for comparison. Only saxagliptin and vildagliptin, which both contain a cyanopyrrolidine group, quickly reacted with L-cysteine to enzyme-independently produce thiazolinic acid metabolites. This saxagliptin-cysteine adduct was also found in saxagliptin-administered male Sprague-Dawley rats. In addition, this study newly identified cysteinyl glycine conjugates of saxagliptin and 5-hydroxysaxagliptin. The observed metabolic pathways were hydroxylation and conjugation with cysteine, glutathione, sulfate, and glucuronide. In summary, we determined four new thiazoline-containing thiol metabolites (cysteine and cysteinylglycine conjugates of saxagliptin and 5-hydroxysaxagliptin) in saxagliptin-administered male rats. Our results reveal that saxagliptin can covalently bind to the thiol groups of cysteine residues of endogenous proteins in vivo, indicating the potential for saxagliptin to cause drug-induced liver injury.

11.
Exp Mol Med ; 56(1): 100-109, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38182653

RÉSUMÉ

Soluble receptors are soluble forms of receptors found in the extracellular space. They have emerged as pivotal regulators of cellular signaling and disease pathogenesis. This review emphasizes their significance in cancer as diagnostic/prognostic markers and potential therapeutic targets. We provide an overview of the mechanisms by which soluble receptors are generated along with their functions. By exploring their involvement in cancer progression, metastasis, and immune evasion, we highlight the importance of soluble receptors, particularly soluble cytokine receptors and immune checkpoints, in the tumor microenvironment. Although current research has illustrated the emerging clinical relevance of soluble receptors, their therapeutic applications remain underexplored. As the landscape of cancer treatment evolves, understanding and targeting soluble receptors might pave the way for novel strategies for cancer diagnosis, prognosis, and therapy.


Sujet(s)
Pertinence clinique , Tumeurs , Humains , Tumeurs/anatomopathologie , Immunothérapie , Microenvironnement tumoral
12.
Int J Biol Macromol ; 256(Pt 2): 128471, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38040154

RÉSUMÉ

Bread staling adversely affects the quality of bread, but starch modification by enzymes can counteract this phenomenon. Glycogen branching enzymes (GBEs) used in this study were isolated from Deinococcus geothermalis (DgGBE), Escherichia coli (EcGBE), and Vibrio vulnificus (VvGBE). These enzymes were characterized and applied for starch dough modification to determine their role in improving bread quality. First, the branching patterns, activity on amylose and amylopectin, and thermostability of the GBEs were determined and compared. EcGBE and DgGBE exhibited better thermostable characteristics than VvGBE, and all GBEs exhibited preferential catalysis of amylopectin over amylose but different degrees. VvGBE and DgGBE produced a large number of short branches. Three GBEs degraded the starch granules and generated soluble polysaccharides. Moreover, the maltose was increased in the starch slurry but most significantly in the DgGBE treatment. Degradation of the starch granules by GBEs enhanced the maltose generation of internal amylases. When used in the bread-making process, DgGBE and VvGBE increased the dough and bread volume by 9 % and 17 %, respectively. The crumb firmness and retrogradation of the bread were decreased and delayed significantly more in the DgGBE bread. Consequently, this study can contribute to understanding the detailed roles of GBEs in the baking process.


Sujet(s)
1,4-alpha-Glucan branching enzyme , Amylopectine , Amylopectine/métabolisme , Amylose/métabolisme , 1,4-alpha-Glucan branching enzyme/métabolisme , Pain , Maltose , Amidon/métabolisme , Glycogène
13.
Angew Chem Int Ed Engl ; 62(50): e202314148, 2023 Dec 11.
Article de Anglais | MEDLINE | ID: mdl-37874975

RÉSUMÉ

Increasing the chemical diversity of organic semiconductors is essential to develop efficient electronic devices. In particular, the replacement of carbon-carbon (C-C) bonds with isoelectronic boron-nitrogen (B-N) bonds allows precise modulation of the electronic properties of semiconductors without significant structural changes. Although some researchers have reported the preparation of B2 N2 anthracene derivatives with two B-N bonds, no compounds with continuous multiple BN units have been prepared yet. Herein, we report the synthesis and characterization of a B2 N2 anthracene derivative with a BNBN unit formed by converting the BOBN unit at the zigzag edge. Compared to the all-carbon analogue 2-phenylanthracene, BNBN anthracene exhibits significant variations in the C-C bond length and a larger highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap. The experimentally determined bond lengths and electronic properties of BNBN anthracene are confirmed through theoretical calculations. The BOBN anthracene organic light-emitting diode, used as a blue host, exhibits a low driving voltage. The findings of this study may facilitate the development of larger acenes with multiple BN units and potential applications in organic electronics.

14.
J Phys Chem A ; 127(28): 5815-5822, 2023 Jul 20.
Article de Anglais | MEDLINE | ID: mdl-37432658

RÉSUMÉ

We re-examined the existence of planar tetracoordinate F (ptF) atoms, which was proposed recently by using high-level ab initio methods such as coupled-cluster singles and doubles with perturbative triples (CCSD(T)) with large basis sets. Our calculations indicate that the planar structures of FIn4+ (D4h), FTl4+ (D4h), FGaIn3+ (C2V), FIn2Tl2+ (D2h), FIn3Tl+ (C2V), and FInTl3+ (C2V) are not the minimum energy states; by contrast, they are transition states. Density functional theory calculations overestimate the size of the cavity formed by the four peripheral atoms, leading to erroneous conclusions regarding the existence of ptF atoms. Our analysis suggests that the preference for non-planar structures in the six cations studied is not due to the pseudo Jahn-Teller effect. Additionally, spin-orbit coupling does not alter the main conclusion that the ptF atom does not exist. If sufficiently large cavity formation by group 13 elements to accommodate the central F- ion is guaranteed, then the existence of ptF atoms is plausible.

15.
Phys Chem Chem Phys ; 25(26): 17230-17237, 2023 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-37338915

RÉSUMÉ

1,2-Dihydro-1,2-azaborine is an isoelectronic analog of benzene with a B-N substitution, and its unique photoisomerization behavior, which is distinct from that of benzene, has drawn significant attention. To understand the detailed mechanism of azaborine photochemistry considering the dynamical effect and gain a comprehensive understanding of photochemical reactions, we investigated the photoisomerization dynamics of azaborine using nonadiabatic molecular dynamics simulations with Tully's surface hopping algorithm. Herein, the structural and energetic analyses of the trajectories revealed three different paths: direct relaxation (path 1), relaxation via a prefulvene-like intermediate (path 2), and formation of the Dewar isomer as a photoproduct (path 3). Our results confirmed that the photoisomerization of azaborine follows the energetically favored pathway predicted by the previous minimum energy path (MEP) calculations, exclusively forming the Dewar isomer, which is consistent with the experimental observations. Additionally, despite the low quantum yield found in our simulations, the high-level excitation energy calculations support the complete conversion observed in the experiments.

16.
Mol Phylogenet Evol ; 186: 107859, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37329929

RÉSUMÉ

Haplozoans are intestinal parasites of marine annelids with bizarre traits, including a differentiated and dynamic trophozoite stage that resembles the scolex and strobila of tapeworms. Described originally as "Mesozoa", comparative ultrastructural data and molecular phylogenetic analyses have shown that haplozoans are aberrant dinoflagellates; however, these data failed to resolve the phylogenetic position of haplozoans within this diverse group of protists. Several hypotheses for the phylogenetic position of haplozoans have been proposed: (1) within the Gymnodiniales based on tabulation patterns on the trophozoites, (2) within the Blastodiniales based on the parasitic life cycle, and (3) part of a new lineage of dinoflagellates that reflects the highly modified morphology. Here, we demonstrate the phylogenetic position of haplozoans by using three single-trophozoite transcriptomes representing two species: Haplozoon axiothellae and two isolates of H. pugnus collected from the Northwestern and Northeastern Pacific Ocean. Unexpectedly, our phylogenomic analysis of 241 genes showed that these parasites are unambiguously nested within the Peridiniales, a clade of single-celled flagellates that is well represented in marine phytoplankton communities around the world. Although the intestinal trophozoites of Haplozoon species do not show any peridinioid characteristics, we suspect that uncharacterized life cycle stages may reflect their evolutionary history within the Peridiniales.


Sujet(s)
Cestoda , Dinoflagellida , Parasites , Polychaeta , Animaux , Phylogenèse , Cestoda/génétique , Dinoflagellida/génétique
17.
Int J Mol Sci ; 24(9)2023 May 08.
Article de Anglais | MEDLINE | ID: mdl-37176148

RÉSUMÉ

Changes in the DNA damage response (DDR) and cellular metabolism are two important factors that allow cancer cells to proliferate. DDR is a set of events in which DNA damage is recognized, DNA repair factors are recruited to the site of damage, the lesion is repaired, and cellular responses associated with the damage are processed. In cancer, DDR is commonly dysregulated, and the enzymes associated with DDR are prone to changes in ubiquitination. Additionally, cellular metabolism, especially glycolysis, is upregulated in cancer cells, and enzymes in this metabolic pathway are modulated by ubiquitination. The ubiquitin-proteasome system (UPS), particularly E3 ligases, act as a bridge between cellular metabolism and DDR since they regulate the enzymes associated with the two processes. Hence, the E3 ligases with high substrate specificity are considered potential therapeutic targets for treating cancer. A number of small molecule inhibitors designed to target different components of the UPS have been developed, and several have been tested in clinical trials for human use. In this review, we discuss the role of ubiquitination on overall cellular metabolism and DDR and confirm the link between them through the E3 ligases NEDD4, APC/CCDH1, FBXW7, and Pellino1. In addition, we present an overview of the clinically important small molecule inhibitors and implications for their practical use.


Sujet(s)
Tumeurs , Humains , Ubiquitination , Tumeurs/anatomopathologie , Ubiquitin-protein ligases/génétique , Ubiquitin-protein ligases/métabolisme , Altération de l'ADN , Ubiquitine/métabolisme , Réparation de l'ADN
18.
Chemphyschem ; 24(13): e202300048, 2023 Jul 03.
Article de Anglais | MEDLINE | ID: mdl-37040088

RÉSUMÉ

The photochemical reaction mechanism underlying the intramolecular H-transfer of the H2 C3 O+ ⋅ radical cation to the H2 CCCO+ ⋅ methylene ketene cation was elucidated using time-dependent density functional theory and high-level ab initio methods. Once the D1 state of H2 C3 O+ ⋅ is populated, the reaction proceeds to form an intermediate (IM) in the D1 state (IM4D1 ). The molecular structure of the conical intersection (CI) was optimized using a multiconfigurational ab initio method. The CI is readily accessible because it lies slightly above the IM4D1 in energy. In addition, the gradient difference vector of the CI is almost parallel to the intramolecular H-transfer reaction coordinate. Once the vibration mode of IM4D1 which is parallel to the reaction coordinate is populated, the degeneracy of the CI is readily lifted and H2 CCCO+ ⋅ was formed via a relaxation pathway in the D0 state. Our calculated results clearly describe the photochemical intramolecular H transfer reaction reported in a recent study.

19.
J Chem Phys ; 158(15)2023 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-37094019

RÉSUMÉ

Discovery of a new oxidation state for an element expands its chemistry. A high oxidation state, such as +7, is rare for sp-block elements except for halogens. In this study, we determined that Te can attain a +7 oxidation state through the existence of a distorted octahedron (DOH) structure of TeCl6+ based on coupled cluster singles and doubles with perturbative triples calculations. We propose a new type of isomerization that resembles pseudorotation. The octahedron structure of TeF6+ bearing one elongated axial bond isomerizes to a DOH via an associated pseudorotation.

20.
J Phys Chem Lett ; 14(13): 3103-3110, 2023 Apr 06.
Article de Anglais | MEDLINE | ID: mdl-36951437

RÉSUMÉ

Time-resolved X-ray liquidography (TRXL) has emerged as a powerful technique for studying the structural dynamics of small molecules and macromolecules in liquid solutions. However, TRXL has limited sensitivity for small molecules containing light atoms only, whose signal has lower contrast compared with the signal from solvent molecules. Here, we present an alternative approach to bypass this limitation by detecting the change in solvent temperature resulting from a photoinduced reaction. Specifically, we analyzed the heat dynamics of TRXL data obtained from p-hydroxyphenacyl diethyl phosphate (HPDP). This analysis enabled us to experimentally determine the number of intermediates and their respective enthalpy changes, which can be compared to theoretical enthalpies to identify the intermediates. This work demonstrates that TRXL can be used to uncover the kinetics and reaction pathways for small molecules without heavy atoms even if the scattering signal from the solute molecules is buried under the strong solvent scattering signal.

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