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1.
Development ; 151(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007638

RESUMEN

Vertebrate motile cilia are classified as (9+2) or (9+0), based on the presence or absence of the central pair apparatus, respectively. Cryogenic electron microscopy analyses of (9+2) cilia have uncovered an elaborate axonemal protein composition. The extent to which these features are conserved in (9+0) cilia remains unclear. CFAP53, a key axonemal filamentous microtubule inner protein (fMIP) and a centriolar satellites component, is essential for motility of (9+0), but not (9+2) cilia. Here, we show that in (9+2) cilia, CFAP53 functions redundantly with a paralogous fMIP, MNS1. MNS1 localises to ciliary axonemes, and combined loss of both proteins in zebrafish and mice caused severe outer dynein arm loss from (9+2) cilia, significantly affecting their motility. Using immunoprecipitation, we demonstrate that, whereas MNS1 can associate with itself and CFAP53, CFAP53 is unable to self-associate. We also show that additional axonemal dynein-interacting proteins, two outer dynein arm docking (ODAD) complex members, show differential localisation between types of motile cilia. Together, our findings clarify how paralogous fMIPs, CFAP53 and MNS1, function in regulating (9+2) versus (9+0) cilia motility, and further emphasise extensive structural diversity among these organelles.


Asunto(s)
Axonema , Cilios , Pez Cebra , Animales , Cilios/metabolismo , Cilios/ultraestructura , Pez Cebra/metabolismo , Ratones , Axonema/metabolismo , Axonema/ultraestructura , Dineínas Axonemales/metabolismo , Dineínas Axonemales/genética , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Dineínas/metabolismo
2.
Osteoporos Int ; 35(7): 1249-1259, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38771526

RESUMEN

This large-scale prospective study showed that a significant association between longer duration of daily outdoor walking and reduced osteoporosis risk was found among older adults, particularly among those with a low genetic predisposition to osteoporosis, which highlighted the importance of outdoor walking as a simple, cost-effective adjunct for preventing osteoporosis. PURPOSE: The available cross-sectional data and small-scale studies indicate that outdoor walking benefits bone metabolism. Nevertheless, there is a scarcity of comprehensive prospective research investigating the enduring correlation between outdoor walking and osteoporosis. This study aims to conduct a prospective analysis of the correlation between outdoor walking and osteoporosis while also examining potential variations influenced by genetic susceptibility to osteoporosis. METHODS: 24,700 older adults without osteoporosis at baseline were enrolled. These individuals were followed up until December 31, 2021, during which data on outdoor walking was gathered. The genetic risk score for osteoporosis was comprised of 14 single-nucleotide polymorphisms. RESULTS: 4,586 cases of osteoporosis were identified throughout a median follow-up period of 37.3 months. Those who walked outside for > 30 but ≤ 60 min per day had a hazard ratio (HR) of 0.83 (95% confidence interval (CI): 0.72-0.95) for incident osteoporosis, whereas those who walked outside for > 60 min per day had an HR of 0.60 (95% CI: 0.39-0.92). We found that osteoporosis risk exhibited a declining trend in individuals with low genetic risk. Individuals walking outside for > 60 min per day tended to have the lowest overall osteoporosis risk among those with high genetic risk. CONCLUSIONS: A significant negative correlation exists between an extended period of daily outdoor walking and osteoporosis incidence risk. This correlation is particularly pronounced among individuals with low genetic risk. The results above underscore the significance of outdoor walking as a simple and economical adjunct to public health programs to prevent osteoporosis.


Asunto(s)
Predisposición Genética a la Enfermedad , Osteoporosis , Polimorfismo de Nucleótido Simple , Caminata , Humanos , Femenino , Anciano , Masculino , Caminata/fisiología , Estudios Prospectivos , Osteoporosis/genética , Osteoporosis/epidemiología , Incidencia , Persona de Mediana Edad , Factores de Riesgo , Medición de Riesgo/métodos , Anciano de 80 o más Años , Densidad Ósea/genética , Densidad Ósea/fisiología
3.
Ann Hematol ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38886191

RESUMEN

Diffuse large B-cell lymphoma (DLBCL), accounts for 30-40% of newly diagnosed lymphomas, has an overall cure rate of approximately 60%. Despite previous reports suggesting a negative prognostic association between CCND3 mutations and Burkitt lymphoma, their prognostic implications in DLBCL remain controversial. To investigate this, we evaluated CCND3 mutation status in 2059 DLBCL patient samples from four database (integrated cohort) and additional 167 DLBCL patient samples in our center (JSPH cohort). The mutation was identified in 5.5% (113/2059) of the cases in the integrated cohort, with 86% (97/113) found in exon 5. Furthermore, P284, R271, I290 and Q276 are described as CCND3 mutation hotspots. CCND3 mutation was associated with decreased overall survival (OS) in the integrated cohort (P = 0.0407). Further subgroup analysis revealed that patients diagnosed as EZB subtype DLBCL by LymphGen algorithm with CCND3 mutations had poorer OS than patients diagnosed as EZB subtype without CCND3 mutations (P = 0.0140). Using the next-generation sequencing (NGS) in the JSPH cohort, it was found that both cell cycle and DNA replication pathways were highly upregulated in patients with CCND3 mutations. Our results suggest that CCND3 mutations can serve as a novel prognostic factor in DLBCL pathogenesis. Consequently, the development of personalized therapeutic strategies for DLBCL patients with CCND3 mutations might enhance their prognosis.

4.
J Org Chem ; 89(11): 7812-7820, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38779840

RESUMEN

In this paper, the regioselectivity of electrochemical Co(II)-catalyzed [2 + 2 + 2] cycloaddition of terminal alkynes was investigated using density functional theory. We explored in detail the energy profiles for both 1,2,4- and 1,3,5-regioselectivity pathways and revealed the origin of the regioselectivity. Two kinds of conformational isomers derived from the different coordination modes of alkynes with cobaltacyclopentadiene have been found, which were formed through electrochemically mediated redox processes. The regioselectivity of the reaction depends on the two coordination modes. When the Co(II) center attacks α-C of the third alkyne, while ß2-C in cyclopentadiene bonds to ß-C of the alkyne, the reaction favors the formation of 1,2,4-products. In contrast, when the Co(II) center connects to ß-C of the alkyne, it forms only the 1,3,5-products via [4 + 2] cycloaddition because of the steric repulsion between the bulky ligand on Co(II) and the phenyl group in the alkyne.

5.
Biomed Chromatogr ; 38(8): e5922, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38867488

RESUMEN

This study aims to explore the pharmacological substance basis of Qi Ge Decoction (QG) in antihyperlipidemia through a combination of metabolomics and serum pharmacochemistry. We used ultra-performance liquid chromatography quadrupole-time-of-flight/MS (UPLC Q-TOF/MS) to analyze and identify the chemical constituents of QG in vitro and in blood chemical components. The metabolomics technology was used to analyze serum biomarkers of QG in preventing and treating hyperlipidemia. We constructed a mathematical model of the relationship between constituents absorbed into the blood and endogenous biomarkers and explored the potential therapeutic application of QG for the prevention and treatment of hyperlipidemia. Compared with the model group, the levels of total cholesterol and triglyceride in the QG group were significantly decreased (P < 0.01). A total of 12 chemical components absorbed into the blood were identified, and 48 biomarkers of the hyperlipidemia model were obtained from serum metabolomic analysis, of which 15 metabolites were backregulated after QG intervention. Puerarin, hesperetin, puerarin xyloside, calycosin, and monohydroxy-tetramethoxyflavone had a high correlation with the biomarkers regulated by QG. This study elucidated the material basis of QG in the intervention of hyperlipidemia, thereby facilitating future research aimed at further revealing the pharmacodynamic material basis of QG's antihyperlipidemic effects.


Asunto(s)
Medicamentos Herbarios Chinos , Hiperlipidemias , Hipolipemiantes , Metabolómica , Metabolómica/métodos , Hipolipemiantes/sangre , Hipolipemiantes/farmacocinética , Hipolipemiantes/química , Cromatografía Líquida de Alta Presión/métodos , Animales , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/sangre , Masculino , Biomarcadores/sangre , Ratas , Metaboloma/efectos de los fármacos , Ratas Sprague-Dawley , Espectrometría de Masas/métodos
6.
Biomed Chromatogr ; 38(6): e5865, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38514246

RESUMEN

The aim of this work was to explore the differences between various pharmaceutical processes in combined solutions of a single decoction (QGHBY) and a combined decoction (QGHJY) of Qi-Ge decoction from the perspective of chemical composition changes, so as to further guide the clinical application of drugs. A combined solution of a single decoction and a combined decoction of Astragali Radix, Puerariae Lobatae Radix and Citri Reticulatae Chachiensis Pericarpium was prepared with the same technological parameters. The chemical components of the two were detected and identified based on UPLC-Q-TOF/MS, and the different components were determined by principal component analysis. Eighty-eight compounds were identified in the pharmaceutical solution of Qi-Ge decoction. Principal component analysis revealed 11 different components of QGHBY and QGHJY with the conditions of Variable Importance in Projection (VIP) ≥ 1, fold change ≥ 2 and p < 0.05, among which hesperidin, hesperitin, isosinensetin, sinensetin and 5-demethylnobiletin were the components of Citri Reticulatae Chachiensis Pericarpium. The levels of these 11 different components in QGHJY were higher than those of QGHBY. The combined decoction is beneficial for the dissolution of flavonoids and other chemical components, and there is a significant difference in the content of chemical components between modern herbal concentrate granules and traditional decoctions.


Asunto(s)
Medicamentos Herbarios Chinos , Espectrometría de Masas , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Análisis de Componente Principal , Flavonoides/análisis , Flavonoides/química
7.
Funct Integr Genomics ; 23(3): 248, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474836

RESUMEN

Long noncoding RNAs play important roles in the occurrence and development of many malignant cancers. This study focuses on the effects of LINC01087 on gastric cancer and its underlying mechanism. In the present study, LINC01087 and CAAP1 were found to be upregulated, and miR-135a-5p was diminished in gastric cancer specimens and cells. Inhibition of LINC01087 resulted in cell proliferation inhibition and induced cell apoptosis through the intrinsic apoptosis signaling pathway, as evidenced by the activation of caspase-3 and caspase-9. An investigation of the signaling pathway revealed that the effects on proliferation and apoptosis following LINC01087 knockdown were mediated by suppression of CAAP1. Furthermore, application of a miR-135a-5p inhibitor or overexpression of CAAP1 could attenuate the apoptotic effect achieved by LINC01087 inhibition, confirming the involvement of miR-135a-5p/CAAP1 signaling in the occurrence of gastric cancer. In conclusion, the LINC01087/miR-135a-5p/CAAP1 axis modulates gastric cancer tumorigenesis and pathogenesis and presents new insight into gastric cancer targeted therapy.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Gástricas/genética , Apoptosis/genética , Carcinogénesis , Transducción de Señal , Proliferación Celular , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica
8.
Br J Haematol ; 202(3): 550-565, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37226519

RESUMEN

Lymphocyte proliferation and tumourigenesis are dependent on nucleotide synthesis to support DNA, RNA and phospholipid synthesis. Here, we identified that reprogramming of nucleotide metabolism as an important factor divides mantle cell lymphoma (MCL) into two groups with different transcriptional signalling pathways and varying prognoses. We establish a nucleotide metabolism-related prognostic model that includes six genes with different regression coefficients, which significantly predicts prognosis for MCL patients (p < 0.0001). Of these six genes, de novo CTP synthesis pathway enzyme CTPS1 whose inhibitor (STP938) is already in clinical trials for relapsed/refractory lymphomas (NCT05463263) has the highest regression coefficient. An increase in CTPS1 expression predicts adverse overall survival and progression-free survival with independent prognostic significance in 105 primary MCL samples and GEO database (GSE93291). CRISPR CTPS1 knockout causes DNA damage and proliferation defects in MCL. Additionally, MYC positively regulates CTPS1 expression, and TP53-aberrant and ibrutinib-resistant MCL cells also rely on cytidine metabolism. Furthermore, besides the obvious decreased CTP pool caused by CTPS1 deficiency, CTPS1 inhibition may also induce immune-related responses via activating dsDNA-cGAS-STING pathway, which plays a crucial role in impeding tumour growth in MCL patients.


Asunto(s)
Linfoma de Células del Manto , Humanos , Adulto , Linfoma de Células del Manto/tratamiento farmacológico , Resistencia a Antineoplásicos , Citidina/uso terapéutico , Nucleotidiltransferasas , Nucleótidos/uso terapéutico
9.
Exp Eye Res ; 233: 109561, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37429521

RESUMEN

Adrenaline is a sympathomimetic drug used to maintain pupil dilation and to decrease the risk of bleeding. The aim of this study was to demonstrate if adrenaline could exert antifibrotic effects in glaucoma surgery. Adrenaline was tested in fibroblast-populated collagen contraction assays and there was a dose-response decrease in fibroblast contractility: matrices decreased to 47.4% (P = 0.0002) and 86.6% (P = 0.0036) with adrenaline 0.0005% and 0.01%, respectively. There was no significant decrease in cell viability even at high concentrations. Human Tenon's fibroblasts were also treated with adrenaline (0%, 0.0005%, 0.01%) for 24 h and RNA-Sequencing was performed on the Illumina NextSeq 2000. We carried out detailed gene ontology, pathway, disease and drug enrichment analyses. Adrenaline 0.01% upregulated 26 G1/S and 11 S-phase genes, and downregulated 23 G2 and 17 M-phase genes (P < 0.05). Adrenaline demonstrated similar pathway enrichment to mitosis and spindle checkpoint regulation. Adrenaline 0.05% was also injected subconjunctivally during trabeculectomy, PreserFlo Microshunt and Baerveldt 350 tube surgeries, and patients did not experience any adverse effects. Adrenaline is a safe and cheap antifibrotic drug that significantly blocks key cell cycle genes when used at high concentrations. Unless contraindicated, we recommend subconjunctival injections of adrenaline (0.05%) in all glaucoma bleb-forming surgeries.


Asunto(s)
Glaucoma , Trabeculectomía , Humanos , Glaucoma/tratamiento farmacológico , Glaucoma/genética , Glaucoma/cirugía , Epinefrina/farmacología , Epinefrina/metabolismo , Vasoconstrictores/farmacología , Vasoconstrictores/metabolismo , Genes cdc , Fibroblastos/metabolismo
10.
Ann Hematol ; 102(4): 851-862, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36735075

RESUMEN

The aim of this study was to investigate the prognostic value of low T3 syndrome in follicular lymphoma (FL). A total of 221 FL patients with detailed serum thyroid hormone levels and other complete clinical data were enrolled. Baseline features associated with low T3 syndrome were analyzed and balanced by propensity score matching. Univariate and multivariate regression analyses were performed to determine independent risk factors for progression-free survival (PFS) and overall survival (OS). A receiver operating characteristic (ROC) curve was plotted, and the area under the curve (AUC) was calculated to assess the predictive accuracy of FL international prognostic index FLIPI-1/FLIPI-2 and low T3 syndrome. A total of 22 patients (10.0%) had low T3 syndrome at diagnosis, which was associated with poor PFS and OS in the rituximab era. It is an independent prognostic factor for PFS and OS. Low T3 syndrome and FLIPI-1/FLIPI-2 significantly increased the AUC of PFS and OS compared to FLIPI-1/FLIPI-2 alone. Low T3 is a risk factor for POD24. In conclusion, low T3 syndrome may be a good candidate for predicting the prognosis of CLL in future clinical practice. Our study demonstrates that low T3 syndrome is associated with poorer survival outcomes in FL patients.


Asunto(s)
Síndromes del Eutiroideo Enfermo , Linfoma Folicular , Humanos , Síndromes del Eutiroideo Enfermo/complicaciones , Pronóstico , Rituximab , Supervivencia sin Progresión , Estudios Retrospectivos
11.
Ann Hematol ; 102(9): 2471-2481, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37160794

RESUMEN

EBV-positive diffuse large B-cell lymphoma, not otherwise specified (EBV+ DLBCL-NOS), is an EBV-positive clonal B-cell lymphoid proliferation and circulating EBV-DNA is a great indicator for prognosis among EBV associated disease. In this retrospective study, we report 66 EBV+ DLBCL cases among 2137 DLBCL-NOS cases diagnosed from 2013 to 2021 (prevalence of 6.0%). After a median follow-up of 27 months, progression-free survival (PFS) and overall survival (OS) at 2 years were 39.5% ± 6.2% and 53.6% ± 6.4%, respectively. Multivariate analysis showed that only the biomarker of the positivity of post treatment EBV-DNA had a borderline correlation with shorter PFS and OS (PFS: P = 0.053; OS: P = 0.065). Patients were divided into three subgroups according to dynamic changes of EBV-DNA status: EBV-DNA persistently negative group, EBV-DNA persistently positive group, and EBV-DNA transformed from positive to negative group; among the three groups, patients of the persistently positive group had worst PFS and OS (P = 0.0527 and P = 0.0139, respectively). Decline in EBV copies correlated significantly with treatment response as well. In conclusion, circulating EBV-DNA level played a vital role in prognostic and monitoring marker for EBV+ DLBCL-NOS.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Linfoma de Células B Grandes Difuso , Humanos , Pronóstico , Herpesvirus Humano 4/genética , Estudios de Cohortes , Infecciones por Virus de Epstein-Barr/complicaciones , Estudios Retrospectivos , Pueblos del Este de Asia , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , ADN
12.
J Pineal Res ; 74(3): e12858, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36732033

RESUMEN

Increasing carbon dioxide (CO2 ) promotes photosynthesis and mitigates heat stress-induced deleterious effects on plants, but the regulatory mechanisms remain largely unknown. Here, we found that tomato (Solanum lycopersicum L.) plants treated with high atmospheric CO2 concentrations (600, 800, and 1000 µmol mol-1 ) accumulated increased levels of melatonin (N-acetyl-5-methoxy tryptamine) in their leaves and this response is conserved across many plant species, including Arabidopsis, rice, wheat, mustard, cucumber, watermelon, melon, and hot pepper. Elevated CO2 (eCO2 ; 800 µmol mol-1 ) caused a 6.8-fold increase in leaf melatonin content, and eCO2 -induced melatonin biosynthesis preferentially occurred through chloroplast biosynthetic pathways in tomato plants. Crucially, manipulation of endogenous melatonin levels by genetic means affected the eCO2 -induced accumulation of sugar and starch in tomato leaves. Furthermore, net photosynthetic rate, maximum photochemical efficiency of photosystem II, and transcript levels of chloroplast- and nuclear-encoded photosynthetic genes, such as rbcL, rbcS, rbcA, psaD, petB, and atpA, significantly increased in COMT1 overexpressing (COMT1-OE) tomato plants, but not in melatonin-deficient comt1 mutants at eCO2 conditions. While eCO2 enhanced plant tolerance to heat stress (42°C) in wild-type and COMT1-OE, melatonin deficiency compromised eCO2 -induced thermotolerance in comt1 plants. The expression of heat shock proteins genes increased in COMT1-OE but not in comt1 plants in response to eCO2 under heat stress. Further analysis revealed that eCO2 -induced thermotolerance was closely linked to the melatonin-dependent regulation of reactive oxygen species, redox homeostasis, cellular protein protection, and phytohormone metabolism. This study unveiled a crucial mechanism of elevated CO2 -induced thermotolerance in which melatonin acts as an essential endogenous signaling molecule in tomato plants.


Asunto(s)
Melatonina , Solanum lycopersicum , Termotolerancia , Dióxido de Carbono/metabolismo , Fotosíntesis
13.
J Phys Chem A ; 127(50): 10529-10539, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38054661

RESUMEN

The mechanism of the transition metal manganese complex Mn(PhPNN)(CO)2Br (CA-4) that catalyzed the hydrogenation of the azo (N═N) bond to amines has been investigated using the PBE0 function. The results show that the whole reaction involves three basic processes: (1) the addition of H2 to CA gives IN2, which can hydrogenate the azo (N═N) bond at the later stage; (2) hydrogenation of azobenzene by IN2, which gives 1,2-diphenylhydrazine (PhNHNHPh); and (3) hydrogenation of 1,2-diphenylhydrazine by IN2, which affords aniline (PhNH2). The results suggest that the hydrogenation of CA and hydrogenation of azobenzene by IN2 to afford PhNHNHPh are easy to occur due to the low barriers, and the overall rate-determining step is the formation of IN11 and PhNH2 by breaking the N-N bond in the stage of hydrogenation of 1,2-diphenylhydrazine by IN2, with an energy barrier of 39.1 kcal/mol. The computed results are in good agreement with the experimental results. The mechanism of the azobenzene reaction catalyzed by manganese was analyzed by charge and orbital analysis in detail. The theoretical results provide a deeper understanding of the mechanism and fully explain the experimental facts.

14.
J Phys Chem A ; 127(43): 8985-8993, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37874943

RESUMEN

The donors are key components of organic solar cells (OSCs) and play crucial roles in their photovoltaic performance. Herein, we designed two new donors (BTR-γ-Cl and BTR-γ-F) by finely optimizing small molecule donors (BTR-Cl and BTR-F) with a high performance. The optoelectronic properties of the four donors and their interfacial properties with the well-known acceptor Y6 were studied by density functional theory and time-dependent density functional theory. Our calculations show that the studied four donors have large hole mobility and strong interactions with Y6, where the BTR-γ-Cl/Y6 has the largest binding energy. Importantly, the proportion of charge transfer (CT) states increases at the BTR-γ-Cl/Y6 (50%) and BTR-γ-F/Y6 (45%) interfaces. The newly designed donors are more likely to achieve CT states through intermolecular electric field (IEF) and hot exciton mechanisms than the parent molecules; meanwhile, donors containing Cl atoms are more inclined to produce CT states through the direct excitation mechanism than those containing F atoms. Our results not only provided two promising donors but also shed light on the halogenation effects on donors in OSCs, which might be important to design efficient photovoltaic materials.

15.
Angew Chem Int Ed Engl ; 62(21): e202301592, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36932035

RESUMEN

Metal-polarized aza-ortho-quinone methides (aza-o-QMs) are a unique and efficient handle for azaheterocycle synthesis. Despite great achievements, the potential of these reactive intermediates has not yet been fully exploited, especially the new reaction modes. Herein, we disclosed an unprecedented dearomatization process of metal-polarized aza-o-QMs, affording transient dearomatized spiroaziridine intermediates. Based on this serendipity, we accomplished three sequential dearomatization-rearomatization reactions of benzimidazolines with aza-sulfur ylides, enabling the divergent synthesis of bis-nitrogen heterocycles with high efficiency and flexibility. Moreover, experimental and theoretical studies were performed to explain the proposed mechanisms and observed selectivity. Further cellular evaluation of the dibenzodiazepine products identified a hit compound for new antitumor drugs.

16.
J Am Chem Soc ; 144(43): 19932-19941, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36270010

RESUMEN

Searching for efficient strategies to access structurally novel aminoindolines is of great significance for drug discovery. However, catalytic asymmetric de novo construction of aminoindoline scaffolds with functionality primed for diversification still remains elusive. Here, we report a Cu-catalyzed asymmetric cyclization of ethynyl benzoxazinones with amines, producing chiral 3-aminoindolines in good yield and with high enantioselectivity (up to 97% yield and 98:2 er). Moreover, a radical-mediated sulfonyl migration of these products was unexpectedly found, further affording new chiral 3-aminoindolines bearing alkenyl sulfonyl groups with retained enantiopurity (up to 84% yield and 98:2 er). Bioactivity evaluations indicate that these 3-aminoindolines show notable antitumor activities and chirality is proven to have a significant impact on their antitumor activity.


Asunto(s)
Aminas , Ciclización , Estereoisomerismo , Catálisis
17.
J Am Chem Soc ; 144(14): 6442-6452, 2022 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-35363483

RESUMEN

The enantioconvergent radical C(sp3)-C(sp2) cross-coupling of alkyl halides with alkenylboronate esters is an appealing tool in the assembly of synthetically valuable enantioenriched alkenes owing to the ready availability, low toxicity, and air/moisture stability of alkenylboronate esters. Here, we report a copper/chiral N,N,N-ligand catalytic system for the enantioconvergent cross-coupling of benzyl/propargyl halides with alkenylboronate esters (>80 examples) with good functional group tolerance. The key to the success is the rational design of hemilabile N,N,N-ligands by mounting steric hindrance at the ortho position of one coordinating quinoline ring. Thus, the newly designed ligand could not only promote the radical cross-coupling process in the tridentate form but also deliver enantiocontrol over highly reactive alkyl radicals in the bidentate form. Facile follow-up transformations highlight its potential utility in the synthesis of various enantioenriched building blocks as well as in the late-stage functionalization for drug discovery.


Asunto(s)
Cobre , Ésteres , Alquenos , Catálisis , Ligandos
18.
Biochem Cell Biol ; 100(3): 213-222, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35263194

RESUMEN

Breast cancer is the most common malignant tumour in women. Our research on alloimperatorin from Angelica dahurica showed that alloimperatorin inhibited breast cancer cell viability in a concentration- and time-dependent manner; it also showed that apoptosis and ferroptosis inhibitors significantly weakened the antisurvival effect of alloimperatorin. Alloimperatorin clearly induced breast cancer cell apoptosis and increased the activities of caspase-3, caspase-8, caspase-9, and poly (ADP-ribose) polymerase; it also caused significant mitochondrial shrinkage, promoted the accumulation of Fe2+, reactive oxygen species, and malondialdehyde, and significantly reduced mRNA and protein expression levels of SLC7A11 and GPX4, indicating that alloimperatorin induces ferroptosis. In addition, alloimperatorin significantly promoted Kelch-like ECH-associated protein 1 (Keap1) expression; although it did not affect the expression of PGAM5 (mitochondrial serine/threonine protein phosphatase) and apoptosis-inducing factor mitochondria associated 1 (AIFM1), it significantly reduced the phosphorylation level of AIFM1. After downregulating the expression of Keap1, PGAM5, or AIFM1, the inhibitory effect of alloimperatorin on cell viability was significantly weakened, indicating that alloimperatorin regulates the Keap1/PGAM5/AIFM1 pathway to promote oxeiptosis. Alloimperatorin significantly inhibited the invasion of breast cancer cells, while Keap1 siRNA or GPX4 overexpression vectors significantly enhanced cell invasion and effectively reversed the anti-invasive effect of alloimperatorin. Therefore, alloimperatorin induces breast cancer cell apoptosis, ferroptosis, and oxeiptosis, thereby inhibiting cell growth and invasion.


Asunto(s)
Neoplasias de la Mama , Ferroptosis , Apoptosis , Neoplasias de la Mama/patología , Femenino , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo
19.
Anal Chem ; 94(17): 6430-6435, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35446014

RESUMEN

We have proposed a universal label-free fluorescent nanofilm sensor based on surface plasmon coupled emission (SPCE). A metal-dye-dielectric (MDD) structure was fabricated to mediate the label-free monitoring based on SPCE. The nonfluorescent dielectric film smartly borrowed the fluorescence signal from the bottom dye layer and led to a new SPCE response through the adjacent metal film. The fluorescence emission angle and polarization strongly depended on the thickness of the nonfluorescent dielectric film on the MDD structure. As a demonstration, the growth of a two-dimensional zeolitic imidazolate framework film (ZIF-L) was in situ monitored in the liquid phase by MDD-SPCE for the first time. The label-free fluorescent sensors are facilely prepared by a spin coating technique, with the potential to be widely spread for in situ studies, especially toward nanomaterial growth processes.


Asunto(s)
Estructuras Metalorgánicas , Nanoestructuras , Zeolitas , Colorantes Fluorescentes/química , Nanoestructuras/química , Resonancia por Plasmón de Superficie/métodos
20.
Opt Express ; 30(5): 6556-6565, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299437

RESUMEN

Lithium niobate-on-insulator (LNOI) has recently emerged as a promising material platform for high-density and advanced photonics integrated circuits (PICs). And single-mode waveguides (SMW) are the most basic building blocks for structuring various PICs. In this paper, single-mode conditions (SMCs) for shallowly etched LNOI rib waveguides in x-cut LNOI wafer are investigated with the finite element method (FEM) in consideration of the lateral leakage and the magic width for the first time, to our best knowledge. Our results indicate that due to the lateral leakage and the magic width these shallowly etched x-cut LNOI rib waveguides have unique and complex SMCs. Our method and results provide a guidance in designing low-loss LNOI SMW and high-performance PICs.

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