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1.
PLoS Genet ; 19(9): e1010927, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37733784

RESUMEN

The emergence of fungicide resistance severely threatens crop production by limiting the availability and application of established fungicides. Therefore, it is urgent to identify new fungicidal targets for controlling plant diseases. Here, we characterized the function of a conserved homoserine O-acetyltransferase (HOA) from the rice blast fungus Magnaporthe oryzae that could serve as the candidate antifungal target. Deletion of the MoMET2 and MoCYS2 genes encoding HOAs perturbed the biosynthesis of methionine and S-adenyl methionine, a methyl group donor for epigenetic modifications, and severely attenuated the development and virulence of M. oryzae. The ∆Momet2 mutant is significantly increased in 5-methylcytosine (5mC) modification that represses the expression of genes required for pathogenicity, including MoGLIK and MoCDH-CYT. We further showed that host-induced gene silencing (HIGS) targeting MoMET2 and MoCYS2 effectively controls rice blasts. Our studies revealed the importance of HOA in the development and virulence of M. oryzae, which suggests the potential feasibility of HOA as new targets for novel anti-rice blast measurements.


Asunto(s)
Magnaporthe , Oryza , Virulencia/genética , Oryza/metabolismo , Metionina/genética , Expresión Génica , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
2.
Am J Pathol ; 194(2): 296-306, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38245251

RESUMEN

This study investigates the regulatory mechanisms of synovial macrophages and their polarization in the progression of temporomandibular joint osteoarthritis (TMJOA). Macrophage depletion models were established by intra-articular injection of clodronate liposomes and unloaded liposomes. TMJOA was induced by intra-articular injection of 50 µL Complete Freund's Adjuvant and the surgery of disc perforation. The contralateral joint was used as the control group. The expression of F4/80, CD86, and CD206 in the synovium was detected by immunofluorescence staining analysis. Hematoxylin and eosin staining and TMJOA synovial score were detected to show the synovial changes in rat joints after TMJOA induction and macrophage depletion. Changes in rat cartilage after TMJOA induction and macrophage depletion were shown by safranin fast green staining. The bone-related parameters of rats' joints were evaluated by micro-computed tomography analysis. The TMJOA model induced by Complete Freund's Adjuvant injection and disc perforation aggravated synovial hyperplasia and showed a significant up-regulation of expression of F4/80-, CD86-, and CD206-positive cells. F4/80, CD86, and CD206 staining levels were significantly decreased in macrophage depletion rats, whereas the synovitis score further increased and cartilage and subchondral bone destruction was slightly aggravated. Macrophages were crucially involved in the progression of TMJOA, and macrophage depletion in TMJOA synoviocytes promoted synovitis and cartilage destruction.


Asunto(s)
Cartílago Articular , Osteoartritis , Sinovitis , Ratas , Animales , Microtomografía por Rayos X , Activación de Macrófagos , Adyuvante de Freund/efectos adversos , Adyuvante de Freund/metabolismo , Liposomas/efectos adversos , Liposomas/metabolismo , Cartílago Articular/metabolismo , Articulación Temporomandibular/metabolismo , Sinovitis/metabolismo , Remodelación Ósea , Osteoartritis/metabolismo
3.
Nano Lett ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38620010

RESUMEN

Regulating the atomic density of single-atom alloys (SAAs) promotes the potential to significantly enhance the electrocatalytic activity. However, conventional methods for study on the electrocatalytic performance of SAAs versus the intersite distance demand exhaustive experiments and characterization. Herein, we present a combinatorial synthesis and analysis method to investigate the intersite distance effect of SAA electrocatalysts. We employ single-nanoparticle collision electrochemistry to realize in situ electrodeposition of a precisely tunable Au atomic density onto individual parent Ag nanoparticles, followed by instantaneous electrocatalytic measurement of the newborn Au-Ag SAAs. In this work, the utility of our method is confirmed by the identification of intersite distance effects of Au-Ag SAAs toward the oxygen reduction reaction. When the site distance between two neighboring Au atoms is 1.9 nm, Au-Ag SAAs exhibit optimal activity. This work provides a simple and efficient method for screening other SAA electrocatalysts with ideal intersite distance at the single-nanoparticle level.

4.
J Cell Mol Med ; 28(7): e18172, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38494837

RESUMEN

M1 macrophage polarization and synovitis play an important role in the pathogenesis of temporomandibular joint osteoarthritis (TMJOA). Reduced molecular weight of hyaluronic acid (HA) in synovial fluid of patients with TMJOA. In addition, high molecular weight hyaluronic acid (HMW-HA) is often used clinically to treat TMJ inflammation. As a pattern recognition receptor of the cytoplasm, ALPK1 was found to be pro-inflammatory in a variety of diseases. However, the relationship of ALPK1, HA and M1 macrophage polarization in TMJ synovitis remains unclear. We aimed to investigate the role of ALPK1 and HA in macrophage polarization and TMJ synovitis and the underlying mechanisms. The results demonstrated that ALPK1 was highly upregulated in the synovial macrophages in the inflamed TMJ synovium of patients. Low molecular weight hyaluronic acid (LMW-HA) promoted the expression of ALPK1 and M1 macrophage-associated genes. Besides, rhALPK1 promoted the expression of M1 macrophage-associated factors and the nuclear translocation of PKM2. Furthermore, ALPK1 knockout mice exhibited limited infiltration of macrophages and decreased expression levels of M1 macrophage-associated genes in CFA-induced TMJ synovitis. While HMW-HA inhibited the expression of ALPK1 and M1 macrophage polarization. Our results elucidated that ALPK1 promoted TMJ synovitis by promoting nuclear PKM2-mediated M1 macrophage polarization, whereas HMW-HA inhibited the expression of ALPK1 as well as M1 macrophage polarization.


Asunto(s)
Osteoartritis , Sinovitis , Humanos , Animales , Ratones , Ácido Hialurónico , Sinovitis/patología , Articulación Temporomandibular/patología , Inflamación/patología , Osteoartritis/metabolismo , Macrófagos/metabolismo , Proteínas Quinasas
5.
J Am Chem Soc ; 146(17): 11592-11598, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630123

RESUMEN

Cocrystal screening and single-crystal growth remain the primary obstacles in the development of pharmaceutical cocrystals. Here, we present a new approach for cocrystal screening, microspacing in-air sublimation (MAS), to obtain new cocrystals and grow high-quality single crystals of cocrystals within tens of minutes. The method possesses the advantages of strong designable ability of devices, user-friendly control, and compatibility with materials, especially for the thermolabile molecules. A novel drug-drug cocrystal of favipiravir (FPV) with salicylamide (SAA) was first discovered by this method, which shows improved physiochemical properties. Furthermore, this method proved effective in cultivating single crystals of FPV-isonicotinamide (FPV-INIA), FPV-urea, FPV-nicotinamide (FPV-NIA), and FPV-tromethamine (FPV-Tro) cocrystals, and the structures of these cocrystals were determined for the first time. By adjusting the growth temperature and growth distance precisely, we also achieved single crystals of 10 different paracetamol (PCA) cocrystals and piracetam (PIR) cocrystals, which underscores the versatility and efficiency of this method in pharmaceutical cocrystal screening.


Asunto(s)
Amidas , Cristalización , Niacinamida , Pirazinas , Niacinamida/química , Pirazinas/química , Amidas/química , Salicilamidas/química , Urea/química , Modelos Moleculares , Cristalografía por Rayos X
6.
Anal Chem ; 96(26): 10772-10779, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38902946

RESUMEN

A simple, sustainable, and sensitive monitoring approach of micro/nanoplastics (MNPs) in aqueous samples is crucial since it helps in assessing the extent of contamination and understanding the potential risks associated with their presence without causing additional stress to the environment. In this study, a novel strategy for qualitative and quantitative determination of MNPs in water by direct solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was proposed for the first time. Spherical poly(methyl methacrylate) (PMMA) and irregularly shaped polyvinyl dichloride (PVDC) were used to evaluate the feasibility and performance of the proposed method. The results demonstrated that both PMMA and PVDC MNPs were efficiently extracted by the homemade SPME coating of nitrogen-doped porous carbons (N-SPCs) and exhibited sufficient thermal decomposition in the GC-MS injection port. Excellent extraction performances of N-SPCs coating for MNPs are attributed to hydrophobic cross-linking, electrostatic forcing, hydrogen bonding, and pore trapping. Methyl methacrylate was identified as the marker for PMMA, while 1,3-dichlorobenzene and 1,3,5-trichlorobenzene were the indicators for PVDC. Under the optimal extraction and decomposition conditions, the proposed method exhibited ultrahigh sensitivity, with a limit of detection of 0.0041 µg/L for PMMA and 0.0054 µg/L for PVDC. Notably, a programmed temperature strategy for the GC-MS injector was developed to discriminate and eliminate the potential interferences of intrinsic indicator compounds. Owing to the integration of sampling, extraction, injection, and decomposition into one step by SPME, the proposed method demonstrates exceptional sensitivity, eliminating the necessity for complex sample pretreatment procedures and the use of organic solvents. Finally, the proposed method was successfully applied in the determination of PMMA and PVDC MNPs in real aqueous samples.

7.
Anal Chem ; 96(5): 2227-2235, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38272489

RESUMEN

Determinations of micro/nanoplastics (MNPs) in environmental samples are essential to assess the extent of their presence in the environment and their potential impact on ecosystems and human health. With the aim to provide a sensitive method with simplified pretreatment steps, cooling-assisted solid-phase microextraction (CA-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) is proposed as a new approach to quantify mass concentrations of MNPs in water and soil samples. The herein proposed CA-SPME method offers the unique advantage of integrating the thermal decomposition of MNPs and enrichment of signature compounds into one step. Poly(methyl methacrylate) (PMMA) was used as a model substance to verify the method performance in this work. Theoretical insights demonstrated that pyrolysis is the rate-determining step during the extraction process and that PMMA is effectively decomposed at 350 °C with an estimated incubation time of 13 min. Eight compounds were identified in the pyrolysis products by CA-SPME-GC-MS with the use of a DVB/CAR/PDMS coating, wherein methyl methacrylate was considered as the best indicator and dimethyl 2-methylenesuccinate was selected as the confirmation compound. Under the optimized conditions, the proposed method exhibited wide linearity (0.5-2000 µg for water and 5-1000 µg for soil) and high sensitivity, with limits of detection of 0.014 and 0.28 µg for water and soil, respectively. Finally, the proposed method was successfully applied for determinations of PMMA MNPs in real water and soil samples with satisfactory recoveries attained. The method only required the employment of a filter membrane for water analysis, while soil samples were analyzed directly without any pretreatment. The solvent-free approach, straightforward operation, and high sensitivity of the proposed method show great potential for the analysis of MNPs in different environmental samples.

8.
BMC Plant Biol ; 24(1): 600, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926811

RESUMEN

BACKGROUND: Delphinium L. represents a taxonomically intricate genus of significant phylogenetic and economic importance in Ranunculaceae. Despite the existence of few chloroplast genome datasets, a comprehensive understanding of genome structures and selective pressures within the genus remains unknown. Furthermore, several taxa in this genus are exclusively found in Xinjiang, China, a region renowned for its distribution and diversity of Chinese and Central Asian Delphinium species. Therefore, investigating the features of chloroplast genomes in this area will provide valuable insights into the evolutionary processes and phylogenetic relationships of the genus. RESULTS: In this study, the eight newly completed chloroplast genomes are examined, ranging in length from 153,979 bp to 154,284 bp. Alongside these, analysing six previously reported taxa re-annotated in Delphinium, 111 unique genes are identified across all samples. Genome structure, distributions of simple sequence repeats and short dispersed repeats, as well as gene content are similar among these Delphinium taxa. Nine hypervariable intergenic spacers and protein coding regions, including ndhF-trnL(TAG), rpl16-intron, rpl33, rps15, rps18, trnK(TTT)-trnQ(TTG), trnP(TGG)-psaJ, trnT(GGT)-psbD and ycf1, are identified among 13 perennial Delphinium. Selective pressure and codon usage bias of all the plastid genes are performed within 14 Delphinium taxa. Phylogenetic analysis based on 14 Delphinium plastomes, alongside two Aconitum (Ranunculaceae) species serving as outgroup taxa, reveals the monophyletic nature of Delphinium. Our findings further discern Delphinium into two distinct clades: perennial species (clade I) and annual species (clade II). In addition, compared with the nrDNA ITS topology, cytological data and morphological characters, D. mollifolium and D. maackianum showed potential involvement in hybridization or polyploidization processes. Excluding these two species, the perennial Delphinium (clade I) exhibits a stronger consistency with the morphology-based system that utilized seed morphology. CONCLUSION: This study represents the first comprehensive analysis of plastomic variations among Delphinium taxa, based on the examination of 14 complete plastomes. The chloroplast genome structure of Delphinium is similar to other angiosperms and possesses the typical quadripartite structure with the conserved genome arrangement and gene features. In addition, the variation of non-coding regions is larger than coding regions of the chloroplast genome. Through DNA sequence divergence across Delphinium plastomes and subsequent phylogenomic analyses ndhF-trnL(TAG) and ycf1 are identified as promising molecular markers. These highly variable loci held significant potential for future phylogenetic and phylogeographic studies on Delphinium. Our phylogenomic analyses based on the whole plastomes, concatenation of 132 unique intergenic spacer regions, concatenation of 77 unique protein-coding genes and nrDNA ITS, all support the monophyly of Delphinium and perennial taxa clusters together into one clade within this genus. These findings provide crucial data for systematic, phylogenomic and evolutionary research in the genus for future studies.


Asunto(s)
Delphinium , Genoma del Cloroplasto , Filogenia , Delphinium/genética , Delphinium/clasificación , China , Ranunculaceae/genética , Ranunculaceae/clasificación
9.
Small ; 20(25): e2309542, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38221683

RESUMEN

Smart luminescent materials that have the ability to reversibly adapt to external environmental stimuli and possess a wide range of responses are continually emerging, which place higher demands on the means of regulation and response sites. Here, europium ions (Eu3+)-directed supramolecular metallogels are constructed by orthogonal self-assembly of Eu3+ based coordination interactions and hydrogen bonding. A new organic ligand (L) is synthesized, consisting of crown ethers and two flexible amide bonds-linked 1,10-phenanthroline moieties to coordinate with Eu3+. Synergistic intermolecular hydrogen bonding in L and Eu3+-L coordination bonding enable Eu3+ and L to self-assemble into shape-persistent 3D coordination metallogels in MeOH solution. The key to success is the utilization of crown ethers, playing dual roles of acting both as building blocks to build L with C2-symmetrical structure, and as the ideal monomer for increasing the energy transfer from L to Eu3+'s excited state, thus maintaining the excellent luminescence of metallogels. Interestingly, such assemblies show K+, pH, F-, and mechano-induced reversible gel-sol transitions and tunable luminescence properties. Above findings are useful in the studies of molecular switches, dynamic assemblies, and smart luminescent materials.

10.
Small ; : e2311041, 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38342590

RESUMEN

The directional conversion of methane to ethylene is challenging due to the dissociation of the C─H bond and the self-coupling of methyl intermediates. Herein, a novel W/WO3- x catalyst with the fork vein structure consisting of an alternating arrangement of WO3- x and W is developed. Impressively, the catalyst achieves an unprecedented C2 H4 yield of 1822.73 µmol g-1  h-1 , with a selectivity of 82.49%. The enhanced catalytic activity is ascribed to the multifunctional synergistic effect induced by oxygen vacancies and W sites in W/WO3- x . Oxygen vacancies provide abundant coordination of unsaturation sites, which promotes the adsorption and activation of CH4 , thus reducing the dissociation energy barrier of the C─H bond. The CH2 coupling barrier on the metal W surface is significantly lower compared to WO3 , so CH2 can migrate to the W site for coupling. Importantly, the W/WO3- x with high periodicity provides multiple ordered local microelectric fields, and CH2 intermediates with dipole moments undergo orientation polarization and displacement polarization driven by the electric field, thus enabling CH2 migration. This work opens a new avenue for the structural design and modulation of photocatalysts, and provides new perspectives on the migration of methylene between multiple active sites.

11.
J Bioenerg Biomembr ; 56(2): 171-180, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38244155

RESUMEN

To verify the protective effect of circDNAJB6 on Bronchopulmonary dysplasia (BPD) cell and animal models and to explore the possible mechanism of its protective effect. The function of circDNAJB6 was investigated at the cell and animal levels. Nuclear and Cytoplasmic RNA extraction kits and fluorescence in situ hybridization (FISH) were used to explore the distribution of circDNAJB6 in cells, and the potential mechanism of circDNAJB6 was verified by q-PCR, luciferase assays and rescue experiments.CircDNAJB6 is abundant in breast milk exosomes. Overexpression of circDNAJB6 can ameliorate damage in BPD models caused by hyperoxia exposure in vivo and in vitro. Mechanistically, circDNAJB6 can target the downstream DNAJB6 gene and promote the transcription of DNAJB6, exertive a protective effect on the experimental BPD model. Our results showed that circDNAJB6 alleviated damage and inhibited the proliferation of alveolar epithelial cells in the BPD model by promoting transcription of parent gene DNAJB6. Human milk exosome-derived circDNAJB6 provides new directions for preventing and treating BPD.


Asunto(s)
Displasia Broncopulmonar , Exosomas , Animales , Recién Nacido , Femenino , Humanos , Displasia Broncopulmonar/genética , Leche Humana , Animales Recién Nacidos , Exosomas/genética , Hibridación Fluorescente in Situ , Transcripción Genética , Modelos Animales de Enfermedad , Proteínas del Tejido Nervioso/genética , Chaperonas Moleculares/genética , Proteínas del Choque Térmico HSP40/genética
12.
Cancer Cell Int ; 24(1): 166, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734640

RESUMEN

Triple-negative breast cancer (TNBC) is highly malignant and lacks effective biotherapeutic targets. The development of efficient anticancer drugs with low toxicity and few side effects is a hotspot in TNBC treatment research. Although erianin is known to have potent antitumor activity, its regulatory mechanism and target in TNBC have not been fully elucidated, hampering further drug development. This study showed that erianin can significantly inhibit TNBC cell proliferation and migration, promote cell apoptosis, and inhibit the growth of transplanted tumors in mice. Mechanistically, through network pharmacology analysis, molecular docking and cellular thermal shift assays, we preliminarily identified SRC as the cellular target of erianin. Erianin potently inhibited the expression of SRC, which mediated the anticancer effect of erianin in TNBC. Moreover, erianin can downregulate the expression of genes related to cholesterol synthesis and uptake by targeting SRC, interfering with cholesterol levels in TNBC, thereby inhibiting the progression of TNBC in vivo and in vitro. Taken together, our results suggest that erianin may inhibit the progression of TNBC by suppressing SRC-mediated cholesterol metabolism, and erianin has the great potential to be an effective treatment for TNBC patients.

13.
Ann Hematol ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38519605

RESUMEN

Acute myeloid leukemia (AML) patients with DNA methyltransferase 3A (DNMT3A) mutation display poor prognosis, and targeted therapy is not available currently. Our previous study identified increased expression of Exportin1 (XPO1) in DNMT3AR882H AML patients. Therefore, we further investigated the therapeutic effect of XPO1 inhibition on DNMT3AR882H AML. Three types of DNMT3AR882H AML cell lines were generated, and XPO1 was significantly upregulated in all DNMT3AR882H cells compared with the wild-type (WT) cells. The XPO1 inhibitor selinexor displayed higher potential in the inhibition of proliferation, promotion of apoptosis, and blockage of the cell cycle in DNMT3AR882H cells than WT cells. Selinexor also significantly inhibited the proliferation of subcutaneous tumors in DNMT3AR882H AML model mice. Primary cells with DNMT3A mutations were more sensitive to selinexor in chemotherapy-naive AML patients. RNA sequencing of selinexor treated AML cells revealed that the majority of metabolic pathways were downregulated after selinexor treatment, with the most significant change in the glutathione metabolic pathway. Glutathione inhibitor L-Buthionine-(S, R)-sulfoximine (BSO) significantly enhanced the apoptosis-inducing effect of selinexor in DNMT3AWT/DNMT3AR882H AML cells. In conclusion, our work reveals that selinexor displays anti-leukemia efficacy against DNMT3AR882H AML via downregulating glutathione pathway. Combination of selinexor and BSO provides novel therapeutic strategy for AML treatment.

14.
Cell Commun Signal ; 22(1): 278, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762737

RESUMEN

BACKGROUND: While de novo cholesterol biosynthesis plays a crucial role in chemotherapy resistance of colorectal cancer (CRC), the underlying molecular mechanism remains poorly understood. METHODS: We conducted cell proliferation assays on CRC cells with or without depletion of squalene epoxidase (SQLE), with or without 5-fluorouracil (5-FU) treatment. Additionally, a xenograft mouse model was utilized to explore the impact of SQLE on the chemosensitivity of CRC to 5-FU. RNA-sequencing analysis and immunoblotting analysis were performed to clarify the mechanism. We further explore the effect of SQLE depletion on the ubiquitin of NF-κB inhibitor alpha (IκBα) and (S)-2,3-epoxysqualene on the binding of IκBα to beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC) by using immunoprecipitation assay. In addition, a cohort of 272 CRC patients were selected for our clinical analyses. RESULTS: Mechanistically, (S)-2,3-epoxysqualene promotes IκBα degradation and subsequent NF-κB activation by enhancing the interaction between BTRC and IκBα. Activated NF-κB upregulates the expression of baculoviral IAP repeat containing 3 (BIRC3), sustains tumor cell survival after 5-FU treatment and promotes 5-FU resistance of CRC in vivo. Notably, the treatment of terbinafine, an inhibitor of SQLE commonly used as antifungal drug in clinic, enhances the sensitivity of CRC to 5-FU in vivo. Additionally, the expression of SQLE is associated with the prognosis of human CRC patients with 5-FU-based chemotherapy. CONCLUSIONS: Thus, our finding not only demonstrates a new role of SQLE in chemoresistance of CRC, but also reveals a novel mechanism of (S)-2,3-epoxysqualene-dependent NF-κB activation, implicating the combined potential of terbinafine for 5-FU-based CRC treatment.


Asunto(s)
Neoplasias Colorrectales , Resistencia a Antineoplásicos , Fluorouracilo , FN-kappa B , Escualeno-Monooxigenasa , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Humanos , Escualeno-Monooxigenasa/metabolismo , Escualeno-Monooxigenasa/genética , FN-kappa B/metabolismo , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Animales , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Ratones , Línea Celular Tumoral , Ratones Desnudos , Ratones Endogámicos BALB C , Femenino , Masculino , Proliferación Celular/efectos de los fármacos , Inhibidor NF-kappaB alfa/metabolismo , Inhibidor NF-kappaB alfa/genética , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Inorg Chem ; 63(10): 4783-4789, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38412503

RESUMEN

A mild hydrothermal method was employed to successfully synthesize two new sulfate fluorides, namely, AYSO4F2 (A = K, Rb). They are isomorphic, and both contain [YO4F4] polyhedra and [SO4] tetrahedra in the structure. Theoretical calculations and experimental tests show that AYSO4F2 (A = K, Rb) have large band gaps (7.79 and 7.82 eV) and moderate birefringence (0.015 and 0.02 @ 546.1 nm), with significantly enhanced birefringence and band gaps as compared to that of the single alkali metal sulfates A2SO4 (A = K, Rb). Furthermore, theoretical calculations show that [YO4F4] polyhedra are the main reason for the band gap and birefringence enhancement. This work contributes to the advancement of structural chemistry in the field of rare-earth sulfates, offering a novel approach for the design of sulfates characterized by large birefringence.

16.
Inorg Chem ; 63(1): 852-859, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38112263

RESUMEN

The first compound of cadmium-borate silicate Cd8(BO3)4SiO4, crystallizing in space group P42/n (no. 86), has been successfully synthesized by the conventional high-temperature solution method and melts congruently. The zero-dimensional anionic groups of Cd8(BO3)4SiO4 are isolated [BO3] triangles and isolated [SiO4] tetrahedra which are filled in the framework formed by [CdO6] polyhedra. It has a moderate birefringence (Δn = 0.053 at 546 nm), which is measured by experiment and evaluated by first-principles calculations; meanwhile, the source of birefringence is revealed through the response electronic distribution anisotropy method. The UV-vis-NIR diffuse reflectance spectrum indicates that Cd8(BO3)4SiO4 possesses a wide optical transparency range, with a UV cutoff edge at about 254 nm. This work enriches the structure chemistry of borate silicates, and we discussed the possible methods for the exploration and synthesis of novel optical crystals possessing zero-dimensional anionic groups in the borate silicate system.

17.
Inorg Chem ; 63(3): 1674-1681, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38175192

RESUMEN

Zero-order waveplates are widely used in the manufacture of laser polarizer waves, which are important in polarimetry and the laser industry. However, there are still challenges in designing deep-ultraviolet (DUV) waveplate materials that satisfy large band gaps and small optical anisotropy simultaneously. Herein, three cases of aluminum sulfate fluorides: Na2AlSO4F3, Li4NH4Al(SO4)2F4, and Li6K3Al(SO4)4F4, with novel [AlSO4F3] layers or isolated [AlS2O8F4] trimers were designed and synthesized by the rational assembly of [AlO2F4] and [SO4] groups through a hydrothermal method. Experiments and theoretical calculations imply that these three possess short cutoff edges (λ < 200 nm) and small birefringence (0.0014-0.0076 @ 1064 nm), which fulfils the prerequisite for potential DUV zero-order waveplate materials. This work extends the exploration of DUV zero-order waveplate materials to the aluminum sulfate fluoride systems.

18.
Environ Sci Technol ; 58(24): 10764-10775, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38843113

RESUMEN

The abrasion of synthetic textile fibers is a significant factor in the generation of environmental microplastic fibers (MPFs). The extent to which polymer sponges designed specifically for surface cleaning have a tendency to release MPFs during normal use remains unknown. Here, the tribological behaviors of melamine cleaning sponges (also known as "magic erasers") with different strut densities against metal surfaces of different roughness were investigated using a reciprocating abrader. The MPFs formed by sponge wear under various conditions were characterized in terms of their morphology, composition, and quantity. They were mainly composed of poly(melamine-formaldehyde) polymer with linear or branched fiber morphologies (10-405 µm in length), which were formed through deformation and fracture of the struts within open cells of the sponges, facilitated by friction-induced polymer decomposition. The rate and capability of MPF production generally increased with increasing roughness of the metal surface and density of the struts, respectively. The sponge wear could release 6.5 million MPFs/g, which could suggest a global overall emission of 4.9 trillion MPFs due to sponge consumption. Our study reveals a hitherto unrecognized source of the environmental MPF contamination and highlights the need to evaluate exposure risks associated with these new forms of MPFs.


Asunto(s)
Microplásticos , Polímeros/química , Textiles
19.
Epidemiol Infect ; 152: e44, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477024

RESUMEN

Data on epidemiology trends of paediatric tuberculosis (TB) are limited in China. So, we investigated the clinical and epidemiological profiles in diagnosed TB disease and TB infection patients at Beijing Children's Hospital. Of 3 193 patients, 51.05% had pulmonary TB (PTB) and 15.16% had extrapulmonary TB (EPTB). The most frequent forms of EPTB were TB meningitis (39.05%), pleural TB (29.75%), and disseminated TB (10.33%). PTB patients were significantly younger and associated with higher hospitalization frequency. Children aged 1-4 years exhibited higher risk of PTB and TB meningitis, and children aged 5-12 years had higher risk of EPTB. The proportion of PTB patients increased slightly from 40.9% in 2012 to 65% in 2019, and then decreased to 17.8% in 2021. The percentage of EPTB cases decreased from 18.3% in 2012 to 15.2% in 2019, but increased to 16.4% in 2021. Among EPTB cases, the largest increase was seen in TB meningitis. In conclusion, female and young children had higher risk of PTB in children. TB meningitis was the most frequent forms of EPTB among children, and young children were at high risk of TB meningitis. The distribution of different types of EPTB differed by age.


Asunto(s)
Tuberculosis Meníngea , Tuberculosis Pulmonar , Humanos , Niño , Femenino , Preescolar , Tuberculosis Meníngea/epidemiología , Beijing/epidemiología , Estudios Retrospectivos , Tuberculosis Pulmonar/epidemiología , China/epidemiología
20.
Bioorg Med Chem ; 102: 117660, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38442524

RESUMEN

Werner (WRN) syndrome protein is a multifunctional enzyme with helicase, ATPase, and exonuclease activities that are necessary for numerous DNA-related transactions in the human cell. Recent studies identified WRN as a synthetic lethal target in cancers. In this study, a series of new N-arylquinazoline-4-amine analogs were designed and synthesized based on structure optimization of quinazoline. The structures of the thirty-two newly synthesized compounds were confirmed by 1H NMR, 13C NMR and ESI-MS. The anticancer activity in vitro against chronic myeloid leukemia cells (K562), non-small cell lung cancer cells (A549), human prostate cancer cells (PC3), and cervical cancer cells (HeLa) of the target compounds was evaluated. Among them, the inhibition ratio of compounds 17d, 18a, 18b, 11 and 23a against four cancer cells at 5 µM concentration were more than 50 %. The IC50 values of compounds 18a and 18b were 0.3 ± 0.01 µM and 0.05 ± 0.02 µM in K562 cells respectively, compared with HeLa and A549 cells, 18a and 18b were more sensitive to K562 cells. In addition, the PC3 cells with WRN overexpression (PC3-WRN) was constructed, 18a and 18b and 23a were more sensitive to PC3-WRN cells compared with the control group cells (PC3-NC). Then, the cell viability of the novel WRN inhibitors were further assessed by colony formation assay. Compared with PC3-NC cells, 18b and 23a had obvious inhibitory effect on PC3-WRN cell at 1000 nM. In summary, these results indicated that the compounds 18b and 23a could be WRN protein inhibitor with potent anticancer properties in vitro.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , RecQ Helicasas , Exodesoxirribonucleasas/metabolismo , Células HeLa
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