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1.
J Nat Prod ; 87(6): 1660-1665, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38888514

RESUMEN

Chetocochliodin M (5) containing a rare cage-ring and chetocochliodin N (6) featuring an unusual piperazine-2,3-dione ring system together with known analogues chetomin (1), chetoseminudin C (2), chetocochliodin I (3), and oidioperazine E (4) were targeted for purification from the fungus Chaetomium cochliodes using a UPLC-Q-TOF-MS/MS approach. The structures of the new compounds were elucidated using HR-ESI-MS, NMR, and ECD spectra. Compounds 1, 3, and 6 exhibited strong cytotoxic activities against A549 and HeLa cancer cell lines.


Asunto(s)
Chaetomium , Espectrometría de Masas en Tándem , Chaetomium/química , Humanos , Estructura Molecular , Espectrometría de Masas en Tándem/métodos , Células HeLa , Cromatografía Líquida de Alta Presión/métodos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Células A549 , Piperazinas/farmacología , Piperazinas/química , Piperazinas/aislamiento & purificación
2.
Animals (Basel) ; 14(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38791650

RESUMEN

Klebsiella pneumoniae (K. pneumoniae) is recognized as a zoonotic pathogen with an increasing threat to livestock and poultry. However, research on K. pneumoniae of animal origin remains limited. To address the gap, a comprehensive investigation was carried out by collecting a total of 311 samples from the farms of four animal species (dairy cow, chicken, sheep, and pig) in selected areas of Xinjiang, China. Isolates were identified by khe gene amplification and 16S rRNA gene sequencing. Genotyping of K. pneumonia isolates was performed using wzi typing and multilocus sequence typing (MLST). PCR was employed to identify virulence and resistance genes. An antibiotic susceptibility test was conducted using the Kirby-Bauer method. The findings revealed an isolation of 62 K. pneumoniae strains, with an average isolation rate of 19.94%, with the highest proportion originating from cattle sources (33.33%). Over 85.00% of these isolates harbored six virulence genes (wabG, uge, fimH, markD, entB, and ureA); while more than 75.00% of isolates possessed four resistance genes (blaTEM, blaSHV, oqxA, and gyrA). All isolates exhibited complete resistance to ampicillin and demonstrated substantial resistance to sulfisoxazole, amoxicillin/clavulanic acid, and enrofloxacin, with an antibiotic resistance rate of more than 50%. Furthermore, 48.39% (30/62) of isolates were classified as multidrug-resistant (MDR) strains, with a significantly higher isolation rate observed in the swine farms (66.67%) compared to other farms. Genetic characterization revealed the classification of the 62 isolates into 30 distinct wzi allele types or 35 different sequence types (STs). Notably, we identified K. pneumoniae strains of dairy and swine origin belonging to the same ST42 and wzi33-KL64 types, as well as strains of dairy and chicken origin belonging to the same wzi31-KL31-K31 type. These findings emphasize the widespread occurrence of drug-resistant K. pneumoniae across diverse animal sources in Xinjiang, underscoring the high prevalence of multidrug resistance. Additionally, our results suggest the potential for animal-to-animal transmission of K. pneumoniae and there was a correlation between virulence genes and antibiotic resistance genes. Moreover, the current study provides valuable data on the prevalence, antibiotic resistance, and genetic diversity of K. pneumoniae originating from diverse animal sources in Xinjiang, China.

3.
Chem Commun (Camb) ; 59(99): 14653-14656, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37991800

RESUMEN

A new class of fluorinated cyclopenta[2,1-b:3,4-b']dithiophene (CPDT)-based small molecules, namely YC-oF, YC-mF, and YC-H, are demonstrated as hole-transporting materials (HTMs) for high-performance perovskite solar cells (PSCs). PSCs employing YC-oF as the HTM delivered an excellent efficiency of 22.41% with encouraging long-term stability.

4.
J Glob Health ; 13: 04076, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37622721

RESUMEN

Background: The rapid increase in electronic nicotine product (ENP) use among young people has been a global public health challenge, given the potential harm of ENPs and nicotine dependence. Many countries have recently introduced legislations to regulate ENPs, but the impacts of these policies are poorly understood. This systematic review aims to critically synthesise empirical studies on the effects of global regulations regarding ENPs on the prevalence of use, health outcomes and their determinants, using the 4A marketing mix framework (acceptability, affordability, accessibility and awareness). Methods: Following the PRISMA guideline, we searched PubMed, Embase, Scopus, Web of Science, Academic Search Complete, Business Source Complete, and APA PsycINFO databases from inception until June 14, 2022 and performed citation searches on the included studies. Reviewed literature was restricted to peer-reviewed, English-language articles. We included all pre-post and quasi-experimental studies that evaluated the impacts of e-cigarette policies on the prevalence of ENP use and other health outcomes. A modified Joanna Briggs Institute (JBI) Critical Appraisal checklist for quasi-experimental studies was used for quality assessment. Due to heterogeneity of the included studies, we conducted a narrative synthesis of evidence. Results: Of 3991 unduplicated records screened, 48 (1.2%) met the inclusion criteria, most were from high-income countries in North America and Europe and 26 studies measured self-reported ENPs use. Flavour restrictions significantly decreased youth ENP use and taxation reduced adult use; mixed results were found for the impacts of age restrictions. Indoor vaping restrictions and the European Tobacco Products Directive (TPD) did not seem to reduce ENP use based on existing studies. Changes in determinants such as sales and perceptions corroborated our conclusions. Few studies assessed the impacts of other regulations such as advertising restrictions and retail licensing requirements. Conclusions: Flavour restrictions and taxes have the strongest evidence to support effective control of ENPs, while others need powerful enforcement and meaningful penalties to ensure their effectiveness. Future research should focus on under-examined policies and differential impacts across sociodemographic characteristics and countries. Registration: PROSPERO CRD42022337361.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Nicotina , Adulto , Adolescente , Humanos , Comercio , Bases de Datos Factuales , Electrónica
5.
Aging (Albany NY) ; 15(15): 7616-7636, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37543427

RESUMEN

Both angiogenesis and lncRNAs play crucial roles in the development and progression of breast cancer. Considering the unknown association of angiogenesis and lncRNAs in breast cancer, we aim to identify angiogenesis-related lncRNAs (ARLs) and explore their prognostic value. Here, based on analysis of The Cancer Genome Atlas database, the correlation between ARL and the prognosis and immune infiltration landscape of breast cancer were investigated. Eight ARLs (MAFG-DT, AC097478.1, AL357054.4, AL118556.1, SNHG10, MED14OS, OTUD6B-AS1, and CYTOR) were selected to construct the risk model as a prognostic signature. The survival rate of the patients in the high-risk group was lower than that in the low-risk group. The ARL signature was an independent prognostic predictor, and areas under the curve of 1-, 3-, and 5-year survival were 0.745, 0.695, and 0.699, respectively. The prognostic ARLs were associated with the immune infiltration landscape and could indicate the immune status, immune response, tumor mutational burden, and drug sensitivity of patients with breast cancer. Furthermore, qRT-PCR of clinical samples revealed that OTUD6B-AS1 was correlated with prognostic pathological parameters. OTUD6B-AS1 promoted breast cancer cell proliferation, wound healing, migration, invasion, and human umbilical vein endothelial cells tube formation. Mechanistically, OTUD6B-AS1 regulated EMT- and angiogenesis-related molecules. Taken together, we constructed and verified a robust signature of eight ARLs for the prediction of survival in patients with breast cancer, and the characterization of the immune infiltration landscape. Our findings suggest that OTUD6B-AS1 could be a therapeutic target for patients with breast cancer.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Humanos , Femenino , Neoplasias de la Mama/genética , ARN Largo no Codificante/genética , Pronóstico , Fenómenos Fisiológicos Cardiovasculares , Células Endoteliales de la Vena Umbilical Humana , Microambiente Tumoral/genética
6.
Front Plant Sci ; 14: 1142212, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008457

RESUMEN

Endophytic fungi from desert plants belong to a unique microbial community that has been scarcely investigated chemically and could be a new resource for bioactive natural products. In this study, 13 secondary metabolites (1-13) with diverse carbon skeletons, including a novel polyketide (1) with a unique 5,6-dihydro-4H,7H-2,6-methanopyrano[4,3-d][1,3]dioxocin-7-one ring system and three undescribed polyketides (2, 7, and 11), were obtained from the endophytic fungus Neocamarosporium betae isolated from two desert plant species. Different approaches, including HR-ESI-MS, UV spectroscopy, IR spectroscopy, NMR, and CD, were used to determine the planar and absolute configurations of the compounds. The possible biosynthetic pathways were proposed based on the structural characteristics of compounds 1-13. Compounds 1, 3, 4, and 9 exhibited strong cytotoxicity toward HepG2 cells compared with the positive control. Several metabolites (2, 4-5, 7-9, and 11-13) were phytotoxic to foxtail leaves. The results support the hypothesis that endophytic fungi from special environments, such as desert areas, produce novel bioactive secondary metabolites.

7.
Clin Breast Cancer ; 23(2): 189-198, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36564279

RESUMEN

BACKGROUND: Increasing studies have shown that microRNAs (miRNAs) have great diagnostic value in cancer. Axillary lymph node metastasis (ALNM) is closely related to the prognosis of breast cancer. However, it remains unknown whether miRNAs in whole blood could be promising biomarkers in breast cancer ALNM. METHODS: An miRNA microarray was used to screen potential differentially expressed miRNA candidates in whole blood of three breast cancer patients with ALNM and three without ALNM. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect candidate differentially expressed miRNAs in the whole blood of 109 breast cancer patients. Furthermore, bioinformatics analysis was carried to predict the potential targets and enriched pathway of miRNAs. RESULTS: QRT-PCR validated the fact that miR-367-3p, miR-548aq-5p and miR-4710 are downregulated in breast cancer with ALNM compared to it without ALNM. Receiver operating characteristic (ROC) curve analysis revealed that miR-367-3p, miR-548aq-5p and miR-4710 have good diagnostic values. Notably, the three-miRNA signature showed better predictive value, with an area under ROC curve (AUC) of 0.7414. Bioinformatics analysis revealed that the miRNAs could participate in a complex network and thus be involved in cancer-related pathways. CONCLUSIONS: Our findings support the potential of miR-367-3p, miR-548aq-5p and miR-4710 and the three-miRNA signature as biomarkers for breast cancer with ALNM.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Metástasis Linfática , Biomarcadores de Tumor/genética , MicroARNs/metabolismo , Biomarcadores , Pronóstico , Curva ROC , Perfilación de la Expresión Génica
8.
Nat Prod Res ; 37(18): 3074-3082, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36373778

RESUMEN

Objectives: An ethanol extract of the whole plants of Saussurea medusa had been investigated to find novel anti-inflammatory sesquiterpenoids. Methods: Extensive spectroscopic data and chemical methods were applied to elucidate the structures of the compounds. Results: One new megastigmane sesquiterpenoid (1), along with 11 known analogues (2-12), were obtained from S. medusa. All isolates, except compounds 3 and 6, were mentioned from the studied plant for the first time. Compounds 1, 2, 4, 5, 7, 8 and 12 were firstly isolated from the genus Saussurea. Compounds 2, 9 and 10 were found to inhibit the lipopolysaccharide (LPS)-induced release of NO by RAW264.7 cells with IC50 values ranging from 21.1 ± 1.7 to 46.7 ± 1.9 µM. Furthermore, iNOS expression experiment was performed to examine the interactions between the active compounds and the iNOS enzyme.

9.
Planta Med ; 89(6): 663-673, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36202093

RESUMEN

Five new diarylbutyrolactones and sesquilignans (1A/1B:  - 4: ), including one pair of enantiomers (1A/1B: ), together with 10 known analogues (5:  - 14: ), were isolated from the whole plants of Saussurea medusa. Compound 1: was found to possess an unusual 7,8'-diarylbutyrolactone lignan structure. Separation by chiral HPLC analysis led to the isolation of one pair of enantiomers, (+)-1A: and (-)-1B: . The structures of the new compounds were elucidated by extensive spectroscopic data. All compounds, except compounds 5, 7: and 9: , were isolated from S. medusa for the first time. Moreover, compounds 1:  -  4, 8: and 10:  - 14: had never been obtained from the genus Saussurea previously. Compounds (+)- 1A, 2, 5, 7: , and 9:  - 11: were found to inhibit the lipopolysaccharide (LPS)-induced release of NO by RAW264.7 cells with IC50 values ranging from 10.1 ± 1.8 to 41.7 ± 2.1 µM. Molecular docking and iNOS expression experiments were performed to examine the interactions between the active compounds and the iNOS enzyme.


Asunto(s)
Lignanos , Saussurea , Ratones , Animales , Lipopolisacáridos , Saussurea/química , Simulación del Acoplamiento Molecular , Lignanos/farmacología , Células RAW 264.7
10.
Int J Mol Sci ; 23(22)2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36430559

RESUMEN

Three pairs of novel enantiomeric 8-O-4' type neolignans (1a/1b−3a/3b), together with seven known analogues (4−10), were isolated from the whole plants of Saussurea medusa. Their structures were elucidated by extensive spectroscopic data analysis and electric circular dichroism (ECD) calculations after chiral separations. All compounds were obtained from S. medusa for the first time, and compounds 1−3 and 5−10 had never been obtained from the genus Saussurea previously. The anti-inflammatory activities of the compounds were evaluated by determining their inhibitory activities on the production of NO and inducible nitric oxide synthase (iNOS) expression in LPS-stimulated RAW 264.7 cells. Compounds (+)-1a, (−)-1b and 5−7 inhibited NO production and had IC50 values ranging from 14.3 ± 1.6 to 41.4 ± 3.1 µM. Compound 7 induced a dose-dependent reduction in the expression of iNOS in LPS-treated RAW 264.7 cells. Molecular docking experiments showed that all active compounds exhibited excellent docking scores (<−7.0 kcal/mol) with iNOS. Therefore, compounds (+)-1a, (−)-1b and 5−7 isolated from the whole plants of S. medusa may have therapeutic potential in inflammatory diseases.


Asunto(s)
Lignanos , Saussurea , Simulación del Acoplamiento Molecular , Lipopolisacáridos/toxicidad , Lignanos/química , Antiinflamatorios/farmacología , Antiinflamatorios/química
11.
Opt Express ; 30(22): 39679-39690, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36298914

RESUMEN

A novel integrated surface plasmon resonance (SPR) sensor that combines an optical waveguide platform and an ultra-thin spectrometer is proposed. The core of the proposed method is a special-shaped optical waveguide structure that employs a wedge-shaped incident surface, which changes the position of the total reflection of the incident light on the sagittal plane without affecting the direction of propagation on the tangential plane. The parameters of the sensing module with the integrated SPR sensor and spectrometer module were designed and optimized to achieve higher performance in a compact optical waveguide platform. An experimental system was built based on the theoretical model, and the spectral sensitivity of the system was analyzed before sample detection, and the results showed that the spectral resolution in the working range could reach 9.9 nm. The refractive index sensitivity of this novel SPR sensor was 3186 nm/RIU with good stability by detecting different concentrations of sodium chloride samples. This new structure does not require an external spectrometer, thereby enabling an increase in the compactness of the SPR sensing system. The proposed method can provide a novel idea for the miniaturization of SPR sensors.

12.
Shanghai Kou Qiang Yi Xue ; 31(2): 189-192, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-36110078

RESUMEN

PURPOSE: To assess the prevalence of oral manifestations in a group of allogenic liver, kidney or haematopoietic stem cell transplantation recipients and patients, and analyze the possible oral manifestations associated with the use of 4 immunosuppressive drugs. METHODS: One hundred and eighteen patients submitted to liver, kidney and hematopoietic stem cell transplantation who used tacrolimus, sirolimus,cyclosporine or mycophenolate mofetil were enrolled. Through a questionnaire survey and oral examination, their oral manifestations were recorded, and the possible statistical associations with immunosuppressive drugs were analyzed using SPSS 21.0 software package. RESULTS: The prevalence of oral lichenoid lesions and cheilitis for the group of patients using tacrolimus after transplantation was significantly lower than the group of patients who did not used the agent(P<0.01). The prevalence of oral lichenoid lesions for the group of patients who used cyclosporine was significantly higher than the group of patients who did not used the drug(P<0.05), and the prevalence of cheilitis for the group of patients who used cyclosporine was significantly higher than the group of patients who did not used the drug(P<0.01). The prevalence of oral lichenoid lesions and cheilitis for the group of patients who used tacrolimus was significantly lower than the group of patients who used cyclosporine(P<0.01). The group of patients who used mycophenolate mofetil after transplantation had a significantly lower prevalence of dry mouth than the group of patients who did not used the drug(P<0.01). The prevalence of oral manifestations in patients with sirolimus after transplantation was not significantly reduced. CONCLUSIONS: The use of tacrolimus improved the symptoms of oral lichenoid lesions and cheilitis and the effect was better than cyclosporine after transplantation. The use of mycophenolate mofetil improved dry mouth after organ transplantation.


Asunto(s)
Queilitis , Inmunosupresores , Trasplante de Órganos , Xerostomía , Queilitis/prevención & control , Ciclosporina/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Ácido Micofenólico/uso terapéutico , Sirolimus , Tacrolimus/uso terapéutico , Xerostomía/prevención & control
13.
Front Genet ; 13: 811849, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35664312

RESUMEN

Background: Patterns of liver energy metabolism significantly differ from birth to adult in cattle undergoing change of rumen rumination. However, the genes involve in hepatic energy metabolism during bovine development and how regulate are still unclear. Methods: In this study, 0-day-old newborn calves (0W) and 9-week-old weaned calves (9W) were used to investigate differences in liver glucose metabolism at these stages of calf development. We did this primarily through the quantitation of energy metabolism indicators, then sequencing the liver transcriptome for each group of claves. Results: The transcriptome results showed 979 differentially expressed genes (DEGs), enriched in animal organ development, catabolic process, transmembrane transport. SLC16A1 involved in that and was locked to investigate. We explored the effects of SLC16A1 on glucose and lactate flux in vitro. We identified and verified its target, miR-22-3p, through bioinformatics and luciferase reporter assays. Moreover, this study found that miR-22-3p decreased cell activity by negatively regulating the SLC16A1. Importantly, our result showed the insulin-induced SLC16A1 mRNA expression decreased, regulated by promoter activity rather than miR-22-3p. Conclusions: Our study illustrates the role of SLC16A1 in the liver mediated metabolism of developing calves. These data enrich our knowledge of the regulatory mechanisms of liver mediated glucose metabolism in developing cattle.

14.
Phytochemistry ; 201: 113264, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35679970

RESUMEN

Ten diphenyl ethers (DPEs), including nine undescribed analogs named betaethrins A-I, were isolated from the desert plant endophytic fungus Phoma betae A.B. Frank (Didymellaceae). Their structures were determined mainly by NMR, HR-ESI-MS spectral and X-ray diffraction experiments. Betaethrins D-I possessed different fatty acid chains connected with the B-ring, which was the first report in all DPEs. The shielding effect of the B-ring on H-6 (A-ring) in methyl barceloneate, betaethrin A and betaethrins D-F (asterric acid analogs) was first observed and analyzed, which could differentiate the 1H-NMR chemical shift values of H-4/H-6 without the assistance of 3-OH. An empirical rule was then suggested: the steric hindrance between the A- and B-rings in asterric acid analogs might prevent these two aromatic rings from rotating freely, which led to the 1H-NMR chemical shift value of H-6 being in the high field zone due to the shielding effect of the B-ring on H-6. Based on the empirical rule, the chemical shift values of the A-ring in methyl barceloneate were revised. The possible biosynthesis of these isolates was postulated. Betaethrin H showed moderate cytotoxicity against MCF-7 and HepG2 cancer cell lines. Betaethrins A-F, H and I displayed strong antioxidant activities. These results further implied that endophytic fungi from unique environments, such as desert plants, with few chemical studies are an important resource of undescribed and bioactive metabolites.


Asunto(s)
Ascomicetos , Endófitos , Ascomicetos/química , Endófitos/química , Éteres Fenílicos/química , Phoma , Plantas
15.
Front Microbiol ; 13: 807014, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35356527

RESUMEN

Seco-sativene sesquiterpenoids are an important member of phytotoxins and plant growth regulators isolated from a narrow spectrum of fungi. In this report, eight seco-sativene sesquiterpenoids (1-8) were first analyzed using the UPLC-Q-TOF-MS/MS technique in positive mode, from which their mass fragmentation pathways were suggested. McLafferty rearrangement, 1,3-rearrangement, and neutral losses were considered to be the main fragmentation patterns for the [M+1]+ ions of 1-8. According to the structural features (of different substitutes at C-1, C-2, and C-13) in compounds 1-8, five subtypes (A-E) of seco-sativene were suggested, from which subtypes A, B/D, and E possessed the diagnostic daughter ions at m/z 175, 189, and 203, respectively, whereas subtype C had the characteristic daughter ion at m/z 187 in the UPLC-Q-TOF-MS/MS profiles. Based on the fragmentation patterns of 1-8, several known compounds (1-8) and two new analogues (9 and 10) were detected in the extract of plant pathogen fungus Bipolaris sorokiniana based on UPLC-Q-TOF-MS/MS analysis, of which 1, 2, 9, and 10 were then isolated and elucidated by NMR spectra. The UPLC-Q-TOF-MS/MS spectra of these two new compounds (9 and 10) were consistent with the fragmentation mechanisms of 1-8. Compound 1 displayed moderate antioxidant activities with IC50 of 0.90 and 1.97 mM for DPPH and ABTS+ scavenging capacity, respectively. The results demonstrated that seco-sativene sesquiterpenoids with the same subtypes possessed the same diagnostic daughter ions in the UPLC-Q-TOF-MS/MS profiles, which could contribute to structural characterization of seco-sativene sesquiterpenoids. Our results also further supported that UPLC-Q-TOF-MS/MS is a powerful and sensitive tool for dereplication and detection of new analogues from crude extracts of different biological origins.

16.
Phytochem Anal ; 33(3): 344-354, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34755399

RESUMEN

INTRODUCTION: In addition to the mycotoxin swainsonine, the locoweed endophytic fungus Alternaria oxytropis (Pleosporaceae) also produces a series of rarely reported, highly oxygenated bicyclic guaiane sesquiterpenoids. Few investigations on the electrospray tandem mass fragmentation pattern of this sesquiterpenoid have been reported. OBJECTIVES: We aimed to analyze and detect new guaiane sesquiterpenoid analogues from crude extracts of the locoweed endophytic fungus A. oxytropis by UPLC-Q-TOF-MS/MS experiments. MATERIALS AND METHODS: Oxytropiols A-J (1-10) and the extract of the locoweed endophytic fungus A. oxytropis were analyzed by UPLC-Q-TOF-MS/MS in positive mode. RESULTS: Typical neutral losses, McLafferty rearrangement, 1,2-rearrangement, and 1,3-rearrangement were considered to be the main fragmentation patterns for the [M + H]+ /[M + Na]+ ions of 1-10 by UPLC-Q-TOF-MS/MS experiments, and possible fragmentation pathways of 1-10 were suggested. A unique and undescribed analogue named oxytropiol K (11) was found in the extract based on UPLC-Q-TOF-MS/MS analysis. Compound 11 was isolated and elucidated by NMR spectrometry, and its UPLC-Q-TOF-MS/MS analysis was consistent with the fragmentation pathways of 1-10. CONCLUSION: The results further support that UPLC-Q-TOF-MS/MS is a powerful and sensitive tool for the characterization of known compounds (dereplication) and the detection of new analogues from crude extracts and imply that the locoweed endophytic fungus A. oxytropis, with few chemical investigations, is an important resource for undescribed metabolites.


Asunto(s)
Oxytropis , Sesquiterpenos , Alternaria/química , Alternaria/metabolismo , Cromatografía Líquida de Alta Presión , Oxytropis/microbiología , Sesquiterpenos de Guayano , Espectrometría de Masas en Tándem
17.
Front Chem ; 9: 789249, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900946

RESUMEN

Analysis, purification, and characterization of AFB1 degraded products are vital steps for elucidation of the photocatalytic mechanism. In this report, the UPLC-Q-TOF-MS/MS technique was first coupled with purification and NMR spectral approaches to analyze and characterize degraded products of AFB1 photocatalyzed under UV irradiation. A total of seventeen degraded products were characterized based on the UPLC-Q-TOF-MS/MS analysis, in which seven ones (1-7) including four (stereo) isomers (1,2, 5, and 6) were purified and elucidated by NMR experiments. According to the structural features of AFB1 and degraded products (1-7), the possible photocatalytic mechanisms were suggested. Furthermore, AFB1 and degraded products (1-7) were evaluated against different cell lines. The results indicated that the UPLC-Q-TOF-MS/MS technique combined with purification, NMR spectral experiments, and biological tests was an applicable integrated approach for analysis, characterization, and toxic evaluation of degraded products of AFB1, which could be used to evaluate other mycotoxin degradation processes.

18.
Chem Commun (Camb) ; 57(52): 6444-6447, 2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34096942

RESUMEN

A new cyclopentadithiophene (CPDT)-based organic small molecule serves as an efficient dopant-free hole transport material (HTM) for perovskite solar cells (PSCs). Upon incorporation of two carbazole groups, the resulting CPDT-based HTM (C-CPDT) shows an impressive power conversion efficiency (PCE) of 19.68% with better stability compared with those of spiro-OMeTAD.

19.
J Asian Nat Prod Res ; 23(11): 1068-1076, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33565352

RESUMEN

Polycyclic polyprenylated acylphloroglucinols (PPAPs) were mainly obtained from the plants of Hypericum genus of Guttiferae family, and possessed intriguing chemical structures and appealing biological activities. Two new PPAPs derivatives, hyperacmosin C (1) and hyperacmosin D (2) were isolated from H. acmosepalum. Their structures were established by NMR, HREIMS, and experimental electronic circular dichroism spectra. Besides, compound 1 showed significant hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage and compound 2 could moderately increase the relative glucose consumption.


Asunto(s)
Hypericum , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/farmacología
20.
ACS Appl Mater Interfaces ; 12(45): 50495-50504, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33112130

RESUMEN

Two polycyclic heteroarene derivatives, namely, V-1 and V-2, with a diphenanthro[9,10-b:9',10'-d]thiophene (DPT) core tethered with two diphenylaminophenyl or diphenylamino groups were first synthesized and used as hole-transporting materials (HTMs) in perovskite solar cell (PSC) fabrication. The novel HTMs exhibit appropriate energy-level alignment with the perovskite so as to ensure efficient hole transfer from the perovskite to HTMs. V-2 with the diphenylamino substituent on DPT exhibited impressive photovoltaic performance with a power conversion efficiency of 19.32%, which was higher than that of V-1 (18.60%) and the benchmark 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene (spiro-OMeTAD) (17.99%), presumably because of a better hole extraction, higher hole mobility, and excellent film-forming ability, which were supported by steady-state photoluminescence (PL), time-resolved PL, the hole mobility experiment, scanning electron microscopy, and atomic force microscopy measurements. Meanwhile, V-2-based PSCs exhibited better long-term durability than that with V-1 and the state-of-the-art spiro-OMeTAD, which is ascribable to the excellent surface morphology and hydrophobicity of the film. This systematic study suggests that DPT-based molecules are good potential candidates as HTMs for achieving high-performance PSCs.

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