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1.
Artigo em Inglês | MEDLINE | ID: mdl-39167800

RESUMO

Enhancers are DNA sequences that can strengthen transcription initiation. However, the global identification of plant enhancers is complicated due to uncertainty in the distance and orientation of enhancers, especially in species with large genomes. In this study, we performed self-transcribing active regulatory region sequencing (STARR-seq) for the first time to identify enhancers across the barley genome. A total of 7323 enhancers were successfully identified, and among 45 randomly selected enhancers, over 75% were effective as validated by a dual-luciferase reporter assay system in the lower epidermis of tobacco leaves. Interestingly, up to 53.5% of the barley enhancers were repetitive sequences, especially transposable elements (TEs), thus reinforcing the vital role of repetitive enhancers in gene expression. Both the common active mark H3K4me3 and repressive mark H3K27me3 were abundant among the barley STARR-seq enhancers. In addition, the functional range of barley STARR-seq enhancers seemed much broader than that of rice or maize and extended to ±100 kb of the gene body, and this finding was consistent with the high expression levels of genes in the genome. This study specifically depicts the unique features of barley enhancers and provides available barley enhancers for further utilization.


Assuntos
Elementos Facilitadores Genéticos , Regulação da Expressão Gênica de Plantas , Hordeum , Hordeum/genética , Hordeum/metabolismo , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica de Plantas/genética , Histonas/metabolismo , Histonas/genética , Elementos de DNA Transponíveis/genética , Genoma de Planta/genética , Sequências Repetitivas de Ácido Nucleico/genética , Análise de Sequência de DNA/métodos
2.
Front Cardiovasc Med ; 11: 1413441, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39070554

RESUMO

The research progress of endoplasmic reticulum (ER) stress in atherosclerosis (AS) is of great concern. The ER, a critical cellular organelle, plays a role in important biological processes including protein synthesis, folding, and modification. Various pathological factors may cause ER stress, and sustained or excessive ER stress triggers the unfolded protein response, ultimately resulting in apoptosis and disease. Recently, researchers have discovered the importance of ER stress in the onset and advancement of AS. ER stress contributes to the occurrence of AS through different pathways such as apoptosis, inflammatory response, oxidative stress, and autophagy. Therefore, this review focuses on the mechanisms of ER stress in the development of AS and related therapeutic targets, which will contribute to a deeper understanding of the disease's pathogenesis and provide novel strategies for preventing and treating AS.

3.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38990515

RESUMO

Accurate prediction of molecular properties is fundamental in drug discovery and development, providing crucial guidance for effective drug design. A critical factor in achieving accurate molecular property prediction lies in the appropriate representation of molecular structures. Presently, prevalent deep learning-based molecular representations rely on 2D structure information as the primary molecular representation, often overlooking essential three-dimensional (3D) conformational information due to the inherent limitations of 2D structures in conveying atomic spatial relationships. In this study, we propose employing the Gram matrix as a condensed representation of 3D molecular structures and for efficient pretraining objectives. Subsequently, we leverage this matrix to construct a novel molecular representation model, Pre-GTM, which inherently encapsulates 3D information. The model accurately predicts the 3D structure of a molecule by estimating the Gram matrix. Our findings demonstrate that Pre-GTM model outperforms the baseline Graphormer model and other pretrained models in the QM9 and MoleculeNet quantitative property prediction task. The integration of the Gram matrix as a condensed representation of 3D molecular structure, incorporated into the Pre-GTM model, opens up promising avenues for its potential application across various domains of molecular research, including drug design, materials science, and chemical engineering.


Assuntos
Conformação Molecular , Modelos Moleculares , Desenho de Fármacos , Aprendizado Profundo , Descoberta de Drogas , Algoritmos
4.
Cells ; 13(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38891043

RESUMO

BAX plays an essential role in retinal ganglion cell (RGC) death induced by optic nerve injury. Recently, we developed M109S, an orally bioactive and cytoprotective small compound (CPSC) that inhibits BAX-mediated cell death. We examined whether M109S can protect RGC from optic nerve crush (ONC)-induced apoptosis. M109S was administered starting 5 h after ONC for 7 days. M109S was orally administered in two groups (5 mg/kg twice a day or 7.5 mg/kg once a day). The retina was stained with anti-BRN3A and cleaved Caspase-3 (active Caspase-3) that are the markers of RGC and apoptotic cells, respectively. ONC decreased the number of BRN3A-positive RGC and increased the number of active Caspase-3-expressing apoptotic cells. In ONC-treated retina, there were cells that were double stained with anti-BRN3A and ant-cleaved Caspase-3, indicating that apoptosis in BRN3A-positive RGCs occurred. M109S inhibited the decrease of BRN3A-positive cells whereas it inhibited the increase of active Caspase-3-positive cells in the retina of ONC-treated mice, suggesting that M109S inhibited apoptosis in RGCs. M109S did not induce detectable histological damage to the lungs or kidneys in mice, suggesting that M109S did not show toxicities in the lung or kidneys when the therapeutic dose was used. The present study suggests that M109S is effective in rescuing damaged RGCs. Since M109S is an orally bioactive small compound, M109S may become the basis for a portable patient-friendly medicine that can be used to prevent blindness by rescuing damaged optic nerve cells from death.


Assuntos
Apoptose , Compressão Nervosa , Traumatismos do Nervo Óptico , Células Ganglionares da Retina , Animais , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/metabolismo , Camundongos , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/patologia , Apoptose/efeitos dos fármacos , Masculino , Caspase 3/metabolismo , Camundongos Endogâmicos C57BL , Citoproteção/efeitos dos fármacos , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/patologia
5.
ACS Nano ; 18(22): 14595-14604, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38758185

RESUMO

Defect engineering and nitrogen doping being effective strategies for modulating the surface chemical state of the carbon matrix have been widely explored to promote the catalytic activity in the territory of electrochemical energy storage and conversion devices. However, the controllable synthesis of carbon material with high-density specific defects and high nitrogen doping is still full of challenges. Here, we first synthesize one-dimensional necklace-like nitrogen-doped carbon nanochains (N-CNCs) with abundant defects on carbon fiber paper (CFP) by chemical vapor deposition (CVD) method. The resultant nanostructures are a bunch of interconnected carbon spheres with a hollow structure at the internode and present the complete one-dimensional nanochain configuration. Specifically, the N-CNCs with a corrugated surface possesses high content of sp3 defects (31.2%) and nitrogen (23.6 at %). Combining finite element analysis and experimental results, it reveals that the robust shear field generated by etching gas releasing from thermal decomposition of melamine in situ modulates the CVD process via changing the size and force environment of the metal catalyst droplets for formation of N-CNCs. Benefiting from the high ratio of sp3/sp2 and nitrogen doped on the surface, the N-CNCs@CFP displays a superior electrocatalytic performance for CO2RR, delivering CO Faradaic efficiency of 95.9% and a current density of 23.2 mA cm-2 at -0.86 V vs RHE. This work provides promising synthesis strategy and some inspirations for construction of ultradense and specific defects coupling with nitrogen doping sites into carbon materials to achieve high-efficiency electrocatalysis applications.

6.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38113075

RESUMO

Kinase inhibitors are crucial in cancer treatment, but drug resistance and side effects hinder the development of effective drugs. To address these challenges, it is essential to analyze the polypharmacology of kinase inhibitor and identify compound with high selectivity profile. This study presents KinomeMETA, a framework for profiling the activity of small molecule kinase inhibitors across a panel of 661 kinases. By training a meta-learner based on a graph neural network and fine-tuning it to create kinase-specific learners, KinomeMETA outperforms benchmark multi-task models and other kinase profiling models. It provides higher accuracy for understudied kinases with limited known data and broader coverage of kinase types, including important mutant kinases. Case studies on the discovery of new scaffold inhibitors for membrane-associated tyrosine- and threonine-specific cdc2-inhibitory kinase and selective inhibitors for fibroblast growth factor receptors demonstrate the role of KinomeMETA in virtual screening and kinome-wide activity profiling. Overall, KinomeMETA has the potential to accelerate kinase drug discovery by more effectively exploring the kinase polypharmacology landscape.


Assuntos
Antineoplásicos , Polifarmacologia , Proteínas Serina-Treonina Quinases , Descoberta de Drogas
7.
J Med Internet Res ; 25: e52444, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37988147

RESUMO

As wearable devices, which allow individuals to track and self-manage their health, become more ubiquitous, the opportunities are growing for researchers to use these sensors within interventions and for data collection. They offer access to data that are captured continuously, passively, and pragmatically with minimal user burden, providing huge advantages for health research. However, the growth in their use must be coupled with consideration of their potential limitations, in particular, digital inclusion, data availability, privacy, ethics of third-party involvement, data quality, and potential for adverse consequences. In this paper, we discuss these issues and strategies used to prevent or mitigate them and recommendations for researchers using wearables as part of interventions or for data collection.


Assuntos
Confiabilidade dos Dados , Dispositivos Eletrônicos Vestíveis , Humanos , Coleta de Dados , Privacidade , Pesquisadores
8.
Chin J Nat Med ; 21(11): 842-851, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38035939

RESUMO

Cancer stands as one of the predominant causes of mortality globally, necessitating ongoing efforts to develop innovative therapeutics. Historically, natural products have been foundational in the quest for anticancer agents. Bulbocodin D (BD) and Bulbocodin C (BC), two bibenzyls derived from Pleione bulbocodioides (Franch.) Rolfe, have demonstrated notable in vitro anticancer activity. In human lung cancer A549 cells, the IC50s for BD and BC were 11.63 and 11.71 µmol·L-1, respectively. BD triggered apoptosis, as evidenced by an upsurge in Annexin V-positive cells and elevated protein expression of cleaved-PARP in cancer cells. Furthermore, BD and BC markedly inhibited the migratory and invasive potentials of A549 cells. The altered genes identified through RNA-sequencing analysis were integrated into the CMap dataset, suggesting BD's role as a potential signal transducer and activator of transcription 3 (STAT3) inhibitor. SwissDock and MOE analyses further revealed that both BD and BC exhibited a commendable binding affinity with STAT3. Additionally, a surface plasmon resonance assay confirmed the direct binding affinity between these compounds and STAT3. Notably, treatment with either BD or BC led to a significant reduction in p-STAT3 (Tyr 705) protein levels, regardless of interleukin-6 stimulation in A549 cells. In addition, the extracellular signal-regulated kinase (ERK) was activated after BD or BC treatment. An enhancement in cancer cell mortality was observed upon combined treatment of BD and U0126, the MEK1/2 inhibitor. In conclusion, BD and BC emerge as promising novel STAT3 inhibitors with potential implications in cancer therapy.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Antineoplásicos/química , Células A549 , Apoptose , Linhagem Celular Tumoral , Proliferação de Células
9.
BMC Med ; 21(1): 388, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37814306

RESUMO

BACKGROUND: Dipeptidyl peptidase-4 inhibitors (DPP-4i) have become firmly established in treatment algorithms and national guidelines for improving glycemic control in type 2 diabetes mellitus (T2DM).To report the findings from a multicenter, randomized, double-blind, placebo-controlled phase 3 clinical trial, which was designed to assess the efficacy and safety of a novel DPP-4 inhibitor fotagliptin in treatment-naive patients with T2DM. METHODS: Patients with T2DM were randomized to receive fotagliptin (n = 230), alogliptin (n = 113) or placebo (n = 115) at a 2:1:1 ratio for 24 weeks of double-blind treatment period, followed by an open-label treatment period, making up a total of 52 weeks. The primary efficacy endpoint was to determine the superiority of fotagliptin over placebo in the change of HbA1c from baseline to Week 24. All serious or significant adverse events were recorded. RESULTS: After 24 weeks, mean decreases in HbA1c from baseline were -0.70% for fotagliptin, -0.72% for alogliptin and -0.26% for placebo. Estimated mean treatment differences in HbA1c were -0.44% (95% confidence interval [CI]: -0.62% to -0.27%) for fotagliptin versus placebo, and -0.46% (95% CI: -0.67% to -0.26%) for alogliptin versus placebo, and 0.02% (95%CI: -0.16% to 0.19%; upper limit of 95%CI < margin of 0.4%) for fotagliptin versus alogliptin. So fotagliptin was non-inferior to alogliptin. Compared with subjects with placebo (15.5%), significantly more patients with fotagliptin (37.0%) and alogliptin (35.5%) achieved HbA1c < 7.0% after 24 weeks of treatment. During the whole 52 weeks of treatment, the overall incidence of hypoglycemia was low for both of the fotagliptin and alogliptin groups (1.0% each). No drug-related serious adverse events were observed in any treatment group. CONCLUSIONS: In summary, the study demonstrated improvement in glycemic control and a favorable safety profile for fotagliptin in treatment-naive patients with T2DM. TRIAL REGISTRATION: ClinicalTrail.gov NCT05782192.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Glicemia , Hipoglicemiantes/efeitos adversos , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Método Duplo-Cego , Resultado do Tratamento
10.
J Cheminform ; 15(1): 57, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287071

RESUMO

Three-dimensional (3D) conformations of a small molecule profoundly affect its binding to the target of interest, the resulting biological effects, and its disposition in living organisms, but it is challenging to accurately characterize the conformational ensemble experimentally. Here, we proposed an autoregressive torsion angle prediction model Tora3D for molecular 3D conformer generation. Rather than directly predicting the conformations in an end-to-end way, Tora3D predicts a set of torsion angles of rotatable bonds by an interpretable autoregressive method and reconstructs the 3D conformations from them, which keeps structural validity during reconstruction. Another advancement of our method over other conformational generation methods is the ability to use energy to guide the conformation generation. In addition, we propose a new message-passing mechanism that applies the Transformer to the graph to solve the difficulty of remote message passing. Tora3D shows superior performance to prior computational models in the trade-off between accuracy and efficiency, and ensures conformational validity, accuracy, and diversity in an interpretable way. Overall, Tora3D can be used for the quick generation of diverse molecular conformations and 3D-based molecular representation, contributing to a wide range of downstream drug design tasks.

11.
Front Microbiol ; 14: 1157601, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323895

RESUMO

Mangrove rhizosphere soils host diverse Actinobacteria tolerant to numerous stresses and are inevitably capable of exhibiting excellent biological activity by producing impressive numbers of bioactive natural products, including those with potential medicinal applications. In this study, we applied an integrated strategy of combining phylogenetic diversity, biological activities, and biosynthetic gene clusters (BGCs) screening approach to investigate the biotechnological importance of Actinobacteria isolated from mangrove rhizosphere soils from Hainan Island. The actinobacterial isolates were identifified using a combination of colony morphological characteristics and 16S rRNA gene sequence analysis. Based on the results of PCR-detected BGCs screening, type I and II polyketide synthase (PKS) and non-ribosomal synthetase (NRPS) genes were detected. Crude extracts of 87 representative isolates were subjected to antimicrobial evaluation by determining the minimum inhibitory concentration of each strain against six indicator microorganisms, anticancer activities were determined on human cancer cell lines HepG2, HeLa, and HCT-116 using an MTT colorimetric assay, and immunosuppressive activities against the proliferation of Con A-induced T murine splenic lymphocytes in vitro. A total of 287 actinobacterial isolates affiliated to 10 genera in eight families of six orders were isolated from five different mangrove rhizosphere soil samples, specififically, Streptomyces (68.29%) and Micromonospora (16.03%), of which 87 representative strains were selected for phylogenetic analysis. The crude extracts of 39 isolates (44.83%) showed antimicrobial activity against at least one of the six tested indicator pathogens, especially ethyl acetate extracts of A-30 (Streptomyces parvulus), which could inhibit the growth of six microbes with MIC values reaching 7.8 µg/mL against Staphylococcus aureus and its resistant strain, compared to the clinical antibiotic ciproflfloxacin. Furthermore, 79 crude extracts (90.80%) and 48 (55.17%) of the isolates displayed anticancer and immunosuppressive activities, respectively. Besides, four rare strains exhibited potent immunosuppressive activity against the proliferation of Con A-induced T murine splenic lymphocyte in vitro with an inhibition rate over 60% at 10 µg/mL. Type I and II polyketide synthase (PKS) and non-ribosomal synthetase (NRPS) genes were detected in 49.43, 66.67, and 88.51% of the 87 Actinobacteria, respectively. Signifificantly, these strains (26 isolates, 29.89%) harbored PKS I, PKS II, and NRPS genes in their genomes. Nevertheless, their bioactivity is independent of BGCs in this study. Our findings highlighted the antimicrobial, immunosuppressive, and anticancer potential of mangrove rhizosphere Actinobacteria from Hainan Island and the biosynthetic prospects of exploiting the corresponding bioactive natural product.

12.
Mediators Inflamm ; 2023: 7123568, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124060

RESUMO

Immunotherapy based on immune checkpoint inhibitors (ICIs) is considered to be a promising treatment for stomach adenocarcinoma (STAD), but only a minority of patients benefit from it. It is believed that the poor therapeutic efficacy is attributed to the complex tumor immune microenvironment (TIM) of STAD. Therefore, elucidating the specific regulatory mechanism of TIM in STAD is critical. Previous study suggests that GRP176 may be involved in regulating the pace of circadian behavior, and its role in tumors has not been reported. In this study, we first found that GPR176 was highly expressed in STAD and negatively correlated with patient prognosis. Next, we investigated the relationship between GPR176 and clinical characteristics, and the results showed that the stage is closely related to the level of GPR176. In addition, our further analysis found that GRP176 expression level was significantly correlated with chemotherapeutic drug sensitivity and ICI response. KEGG and GO analyses showed that GPR176 might be involved in stromal remodeling of STAD. Furthermore, we analyzed the association between GPR176 expression and immune implication, and the results revealed that GPR176 was negatively related to the infiltration of various immune cells. Interestingly, GPR176 induced the conversion of TIM while reducing the tumor immune burden (TMB). The expression of GRP176 is closely related to the level of various immunomodulators. Moreover, we performed univariate and multivariate regression analyses on the immunomodulators and finally obtained 4 genes (CRCR4, TNSF18, PDCD1, and TGFB1). Then, we constructed a GRP176-related immunomodulator prognostic model (GRIM) based on the above 4 genes, which was validated to have good predictive power. Finally, we developed a nomogram based on the risk score of GRIM and verified its accuracy. These results suggested that GPR176 is closely related to the prognosis and TIM of STAD. GPR176 may be a new potential target for immunotherapy in STAD.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Prognóstico , Biomarcadores , Adenocarcinoma/genética , Neoplasias Gástricas/genética , Adjuvantes Imunológicos , Microambiente Tumoral
13.
Mediators Inflamm ; 2023: 7992140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152370

RESUMO

Liver hepatocellular carcinoma (LIHC) is a highly lethal malignant tumor originating from the digestive system, which is a serious threat to human health. In recent years, immunotherapy has shown significant therapeutic effects in the treatment of LIHC, but only for a minority of patients. The basement membrane (BM) plays an important role in the occurrence and development of tumors, including LIHC. Therefore, this study is aimed at establishing a risk score model based on basement membrane-related genes (BMRGs) to predict patient prognosis and response to immunotherapy. First, we defined three patterns of BMRG modification (C1, C2, and C3) by consensus clustering of BMRG sets and LIHC transcriptome data obtained from public databases. Survival analysis showed that patients in the C2 group had a better prognosis, and Gene Set Variation Analysis (GSVA) revealed that the statistically significant pathways were mainly enriched in the C2 group. Moreover, we performed Weighted Correlation Network Analysis (WGCNA) on the above three subgroups and obtained 179 intersecting genes. We further applied function enrichment analyses, and the results demonstrated that they were mainly enriched in metabolism-related pathways. Furthermore, we conducted the LASSO regression analysis and obtained 4 BMRGs (MPV17, GNB1, DHX34, and MAFG) that were significantly related to the prognosis of LIHC patients. We further constructed a prognostic risk score model based on the above genes, which was verified to have good predictive performance for LIHC prognosis. In addition, we analyzed the correlation between the risk score and the tumor immune microenvironment (TIM), and the results showed that the high-risk scoring group tended to be in an immunosuppressed status. Finally, we investigated the relationship between the risk score and LIHC immune function. The results demonstrated that the risk score was closely related to the expression levels of multiple immune checkpoints. Patients in the low-risk group had significantly higher IPS scores, and patients in the high-risk group had lower immune escape and TIDE score. In conclusion, we established a novel risk model based on BMRGs, which may serve as a biomarker for prognosis and immunotherapy in LIHC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas/genética , Membrana Basal , Prognóstico , Microambiente Tumoral , RNA Helicases
14.
Chem Commun (Camb) ; 59(22): 3261-3264, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36815681

RESUMO

A quasi-homogenized miniemulsion system enabled by carbon quantum dot solid nanoparticles for biphasic catalysis is proposed, which breaks existing limits for an immiscibly biphasic system and overcomes issues for large-sized solid particle-stabilized emulsion droplets. The presented Pickering miniemulsion features pH-responsive behavior, finally triggering facile product separation and catalyst recycling in one reaction vessel.

15.
J Pharm Biomed Anal ; 226: 115238, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36645985

RESUMO

Ormosia hosiei Hemsl. et Wils. is an economical and medicinal plant, increasingly cultivated in China; however, its branches and leaves are often pruned as waste. This is the first study focused on the phytochemical profiles and antioxidant, anti-α-glucosidase, anti-tyrosinase, and anti-neuroinflammatory activities of the branches and leaves of O. hosiei. Herein, thirty-seven characteristic compounds were identified by UPLC-MS/MS and twelve were detected for the first time in O. hosiei. Twenty-seven phenolics were further quantified and significant differences in phenolic compositions between the branches and leaves of O. hosiei were observed. The ethanol extracts exhibited promising antioxidant, anti-α-glucosidase, anti-tyrosinase, and anti-neuroinflammatory effects, and the bioactivities significantly correlated with total phenolic content and twelve individual phenolics. Naringin, genistein, vitexin, vitexin-2-O-rhamnoside, syringaresinol and syringaresinol-4-O-ß-D-glucopyranoside can be considered potential quality markers of O. hosiei. Our results provided solid evidence that the branches and leaves of O. hosiei deserve more attention and exploitation, considering the potential to be developed as functional foods or herbal medicines.


Assuntos
Extratos Vegetais , Plantas Medicinais , Extratos Vegetais/química , Antioxidantes/química , Cromatografia Líquida , Espectrometria de Massas em Tandem , Compostos Fitoquímicos/análise , Fenóis/análise , Glucosidases , Folhas de Planta/química
16.
Nat Prod Res ; 37(15): 2486-2492, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35289695

RESUMO

Two new bibenzyls (1 and 2) were isolated from the pseudobulbs of Pleione grandiflora (Rolfe) Rolfe along with six known compounds, including isoarundinin I (3), isoarundinin II (4), bulbocodin D (5), batatasin III (6), 5,3'-dihydroxy- 4-(p-hydroxybenzyl)-3-methoxybibenzyl (7) and shancigusin F (8). Their structures were established on the basis of spectroscopic methods. These compounds showed potent DPPH free radical scavenging effects with IC50 values ranging from 49.72 ± 0.35 µM to 65.41 ± 0.49 µM.


Assuntos
Bibenzilas , Medicamentos de Ervas Chinesas , Orchidaceae , Antioxidantes/farmacologia , Bibenzilas/química , Estrutura Molecular , Medicamentos de Ervas Chinesas/química , Orchidaceae/química
17.
Angew Chem Int Ed Engl ; 62(4): e202216321, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36414544

RESUMO

Electrocatalytic synthesis of aldehydes from alcohols exhibits unique superiorities as a promising technology, in which cascade reactions are involved. However, the cascade reactions are severely limited by the low selectivity resulting from the peroxidation of aldehydes in a traditional liquid-solid system. Herein, we report a novel liquid-liquid-solid system to regulate the selectivity of benzyl alcohol electrooxidation. The selectivity of benzaldehyde increases 200-fold from 0.4 % to 80.4 % compared with the liquid-solid system at a high current density of 136 mA cm-2 , which is the highest one up to date. In the tri-phase system, the benzaldehyde peroxidation is suppressed efficiently, with the conversion of benzaldehyde being decreased from 87.6 % to 3.8 %. The as-produced benzaldehyde can be in situ extracted to toluene phase and separated from the electrolyte to get purified benzaldehyde. This strategy provides an efficient way to efficiently enhance the selectivity of electrocatalytic cascade reactions.

18.
Adv Mater ; 35(14): e2209652, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36575967

RESUMO

Carbon-hybridized hydroxides (CHHs) have been intensively investigated for uses in the energy conversion/storage fields. Nevertheless, the intrinsic structure-activity relationships between carbon and hydroxides within CHHs are still blurry, which hinders the fine modulation of CHHs in terms of practical applications to some degree. This review aims to figure out the intrinsic role of carbon materials in CHHs with a focus on the interface chemistry and the engineering strategy in-between two components. The fundamental effects of the carbon materials in enhancing the charge/mass transfer kinetics are first analyzed, particularly the extra electron pathways for fast charge transfer and the anchoring sites for boosting the mass transfer. Subsequently, the surface-guided/confined effects of carbon materials in CHHs to modify the morphology and tailor the hydroxides, and functional heterojunction for regulating the inner electronic structure are decoupled. The methods to efficiently construct a stable yet robust solid-solid heterointerface are summarized, including oxygen functional groups engrafting, topological defective sites construction and heteroatom incorporation to activate the inert carbon surface. The smart CHHs in some typical energy applications are demonstrated. Additionally, the methodologies that can reveal the hybridization electron configuration between two components are summed up. At last, the perspective and challenges faced by the CHHs for energy-related applications are outlined.

19.
Nat Prod Res ; 37(8): 1321-1327, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34933632

RESUMO

Two new cytisine-like alkaloids, hositisines C (1) and D (2), were isolated from the seeds of Ormosia hosiei along with four known compounds, (-)-tinctorine (3), ß-adenosine (4), 2'-deoxyadenosine (5), and 7, 2', 4'-trihydroxy-5-methoxyisoflavanone (6). Their structures were established using extensive spectroscopic techniques (UV, IR, CD, HRESIMS, 1 D and 2 D NMR). In the cytotoxic activity, compounds 1-3 and 5-fluorouracil (positive control) displayed inhibitory effects against HepG2 cells, exhibiting IC50 values of 44.52 ± 7.83 µM, 111.49 ± 12.76 µM, 127.72 ± 18.67 µM, and 16.37 ± 3.82 µM.


Assuntos
Alcaloides , Fabaceae , Estrutura Molecular , Fabaceae/química , Alcaloides/química , Quinolizinas/farmacologia , Azocinas/farmacologia , Sementes/química
20.
Int J Prosthodont ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36484666

RESUMO

PURPOSE: To evaluate the accuracy of intraoral scanners by comparing the marginal fit of 70 all-ceramic crowns fabricated from both conventional impressions and intraoral scans. MATERIALS AND METHODS: A total of 70 posterior teeth requiring single-crown restorations randomly underwent either intraoral scanning or conventional impression-taking followed by laboratory scanning of the casts in a parallel-group RCT. Subsequently, 70 monolithic all-ceramic crowns were CAD/CAM fabricated; only the impression technique differed. Marginal fit, internal fit, adjustment time required for insertion and occlusal contacts, and visual analog scale (VAS) scores assessing dentists' satisfaction with all of the crowns were clinically evaluated by a blinded and calibrated examiner. Data were analyzed using independent-samples t test and likelihood ratio test or Fisher exact test. All tests were performed with α = .05. RESULTS: The mean marginal fit with intraoral scanning (57.94 ± 22.51 µm) was better than with diagnostic cast scanning (82.98 ± 21.72 µm). The difference was statistically significant (P = .000). The differences in internal fit, adjustment time for crown insertion and occlusal contacts, and VAS scores were also significant, and the secondary outcomes were in favor of intraoral scanning. CONCLUSION: Within the limitations of this clinical trial, CAD/CAM-fabricated single-tooth restorations in the posterior region produced by an intraoral scanning technique using TRIOS was found to be a more accurate and efficient alternative to restorations based on conventional impressions in combination with the laboratory scanning technique.

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