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1.
J Transl Med ; 22(1): 743, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107765

RESUMEN

BACKGROUND: Severe heart failure (HF) has a higher mortality during vulnerable period while targeted predictive tools, especially based on drug exposures, to accurately assess its prognoses remain largely unexplored. Therefore, this study aimed to utilize drug information as the main predictor to develop and validate survival models for severe HF patients during this period. METHODS: We extracted severe HF patients from the MIMIC-IV database (as training and internal validation cohorts) as well as from the MIMIC-III database and local hospital (as external validation cohorts). Three algorithms, including Cox proportional hazards model (CoxPH), random survival forest (RSF), and deep learning survival prediction (DeepSurv), were applied to incorporate the parameters (partial hospitalization information and exposure durations of drugs) for constructing survival prediction models. The model performance was assessed mainly using area under the receiver operator characteristic curve (AUC), brier score (BS), and decision curve analysis (DCA). The model interpretability was determined by the permutation importance and Shapley additive explanations values. RESULTS: A total of 11,590 patients were included in this study. Among the 3 models, the CoxPH model ultimately included 10 variables, while RSF and DeepSurv models incorporated 24 variables, respectively. All of the 3 models achieved respectable performance metrics while the DeepSurv model exhibited the highest AUC values and relatively lower BS among these models. The DCA also verified that the DeepSurv model had the best clinical practicality. CONCLUSIONS: The survival prediction tools established in this study can be applied to severe HF patients during vulnerable period by mainly inputting drug treatment duration, thus contributing to optimal clinical decisions prospectively.


Asunto(s)
Insuficiencia Cardíaca , Modelos de Riesgos Proporcionales , Humanos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/tratamiento farmacológico , Femenino , Masculino , Anciano , Reproducibilidad de los Resultados , Pronóstico , Análisis de Supervivencia , Persona de Mediana Edad , Curva ROC , Algoritmos , Área Bajo la Curva , Bases de Datos Factuales , Aprendizaje Profundo , Índice de Severidad de la Enfermedad
2.
FASEB J ; 37(3): e22824, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36809539

RESUMEN

The present study investigated the effects of 2'-5' oligoadenylate synthetase-like (OASL) on the biological functions of stomach adenocarcinoma (STAD) cells and tumor formation in nude mice. The differential expression levels of OASL in the different cancer types from TCGA dataset were analyzed using gene expression profiling interactive analysis. Overall survival and the receiver operating characteristic were analyzed using the KM plotter and R, respectively. Furthermore, OASL expression and its effects on the biological functions of STAD cells were detected. The possible upstream transcription factors of OASL were predicted using JASPAR. The downstream signaling pathways of OASL were analyzed using GSEA. Tumor formation experiments were performed to evaluate the effect of OASL on tumor formation in nude mice. The results showed that OASL was highly expressed in STAD tissues and cell lines. OASL knockdown markedly inhibited cell viability, proliferation, migration, and invasion and accelerated STAD cell apoptosis. Conversely, OASL overexpression had the opposite effect on STAD cells. JASPAR analysis revealed that STAT1 is an upstream transcription factor of OASL. Furthermore, GSEA showed that OASL activated the mTORC1 signaling pathway in STAD. The protein expression levels of p-mTOR and p-RPS6KB1 were suppressed by OASL knockdown and promoted by OASL overexpression. The mTOR inhibitor, rapamycin, markedly reversed the effect of OASL overexpression on STAD cells. Additionally, OASL promoted tumor formation and increased tumor weight and volume in vivo. In conclusion, OASL knockdown suppressed the proliferation, migration, invasion, and tumor formation of STAD cells by inhibiting the mTOR signaling pathway.


Asunto(s)
2',5'-Oligoadenilato Sintetasa , Adenocarcinoma , Neoplasias Gástricas , Animales , Ratones , Adenocarcinoma/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones Desnudos , Transducción de Señal , Neoplasias Gástricas/genética , Serina-Treonina Quinasas TOR/metabolismo , 2',5'-Oligoadenilato Sintetasa/genética
3.
Eur J Clin Pharmacol ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141126

RESUMEN

PURPOSE: Previous studies showed that long-term use of proton pump inhibitors (PPIs) was associated with cardiovascular events. However, the impact of short-term PPI exposure on intensive care unit (ICU) patients with myocardial infarction (MI) remains largely unknown. This study aims to determine the precise correlation between short-term PPI usage during hospitalization and prognostic outcomes of ICU-admitted MI patients using Medical Information Mart for Intensive Care IV database (MIMIC-IV). METHODS: Propensity score matching (PSM) was applied to adjust confounding factors. The primary study outcome was rehospitalization with mortality and length of stay as secondary outcomes. Binary logistic, multivariable Cox, and linear regression analyses were employed to estimate the impact of short-term PPI exposure on ICU-admitted MI patients. RESULTS: A total of 7249 patients were included, involving 3628 PPI users and 3621 non-PPI users. After PSM, 2687 pairs of patients were matched. The results demonstrated a significant association between PPI exposure and increased risk of rehospitalization for MI in both univariate and multivariate [odds ratio (OR) = 1.157, 95% confidence interval (CI) 1.020-1.313] analyses through logistic regression after PSM. Furthermore, this risk was also observed in patients using PPIs > 7 days, despite decreased risk of all-cause mortality among these patients. It was also found that pantoprazole increased the risk of rehospitalization, whereas omeprazole did not. CONCLUSION: Short-term PPI usage during hospitalization was still associated with higher risk of rehospitalization for MI in ICU-admitted MI patients. Furthermore, omeprazole might be superior to pantoprazole regarding the risk of rehospitalization in ICU-admitted MI patients.

4.
Bioorg Chem ; 143: 107036, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38141330

RESUMEN

This study reports a thermostable glucose-stimulated ß-glucosidase, BglY442, from hot-spring metagenomic data that was cloned and expressed in Escherichia coli BL21 (DE3). The molecular mass of recombinant BglY442 was 69.9 kDa and was used in the production of gardenia blue. The recombinant BglY442 showed its maximum activity at pH 6.0 and 75 °C, maintained 50 % activity at 70 °C for 36 h, presented over 90 % activity in a broad pH range and a wide range of pH stability. Moreover, BglY442 exhibited excellent tolerance toward methanol and ethanol. The specific activity of BglY442 was 235 U/mg at pH 6.0 and 75 °C with 10 mM pNPG as substrate. BglY442 activity increased by over fourfold with 2 M glucose or xylose. Specifically, the enzyme kinetics of BglY442 seem to be non-Michaelis-Menten kinetics or atypical kinetics because the Michaelis-Menten saturation kinetics were not observed with pNPG, oNPG or geniposide as substrates. Under optimum conditions, geniposide was dehydrated by BglY442 and reacted with nine amino acids respectively by the one-pot method. Only the Arg or Met derived pigments showed bright blue, and these two pigments had similar ultraviolet absorption spectra. The OD590 nm of GB was detected to be 1.06 after 24 h with the addition of Arg and 1.61 after 36 h with the addition of Met. The intermediate was elucidated and identified as ginipin. Molecular docking analysis indicated that the enzyme had a similar catalytic mechanism to the reported GH1 Bgls. BglY442 exhibited potential for gardenia blue production by the one-pot method. With outstanding thermostability and glucose tolerance, BglY442 should be considered a potential ß-glucosidase in biotechnology applications.


Asunto(s)
Gardenia , Glucosa , Iridoides , Glucosa/farmacología , Proteínas Recombinantes/metabolismo , beta-Glucosidasa/metabolismo , Metagenoma , Simulación del Acoplamiento Molecular , Concentración de Iones de Hidrógeno , Estabilidad de Enzimas , Especificidad por Sustrato , Temperatura , Cinética
5.
Arch Microbiol ; 205(9): 308, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37594611

RESUMEN

Gastrodia elata needs to establish a symbiotic relationship with Armillaria strains to obtain nutrients and energy. However, the signaling cross talk between G. elata and Armillaria strains is still unclear. During our experiment, we found that the vegetative mycelium of Armillaria gallica 012m grew significantly better in the media containing gibberellic acid (GA3) than the blank control group (BK). To explore the response mechanism, we performed an RNA-sequencing experiment to profile the transcriptome changes of A. gallica 012m cultured in the medium with exogenous GA3. The transcriptome-guided differential expression genes (DEGs) analysis of GA3 and BK showed that a total of 1309 genes were differentially expressed, including 361 upregulated genes and 948 downregulated genes. Some of those DEGs correlated with the biological process, including positive regulation of chromosome segregation, mitotic metaphase/anaphase transition, attachment of mitotic spindle microtubules to kinetochore, mitotic cytokinesis, and nuclear division. These analyses explained that GA3 actively promoted the growth of A. gallica to some extent. Further analysis of protein domain features showed that the deduced polypeptide contained 41 candidate genes of GA receptor, and 27 of them were expressed in our samples. We speculate that GA receptors exist in A. gallica 012m. Comparative studies of proteins showed that the postulated GA receptor domains of A. gallica 012m have a higher homologous correlation with fungi than others based on cluster analysis.


Asunto(s)
Armillaria , Armillaria/genética , Análisis por Conglomerados , Perfilación de la Expresión Génica , Micelio
6.
J Basic Microbiol ; 63(1): 17-25, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36449692

RESUMEN

Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant-fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.


Asunto(s)
Armillaria , Armillaria/genética , Ácidos Indolacéticos/farmacología , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Perfilación de la Expresión Génica
7.
Biochem Cell Biol ; 100(1): 59-67, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34860608

RESUMEN

Angiopoietin-like 2 (Angptl2) is reported to be correlated with cardiovascular diseases, but its role in hypertension remains unclear. This study aimed to investigate the role and potential mechanism of Angptl2 in hypertension. Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) were used to detect the expression of Angptl2. Angiotensin II (Ang II) stimulates vascular smooth muscle cells (VSMCs) to mimic hypertension in vitro. Cell proliferation, migration, and invasion abilities were determined using CCK-8, cell colony formation, wound healing, and transwell assays, respectively. The cell cycle distribution was detected by flow cytometry. The expression of Ki67 was determined by immunofluorescence, and protein expression was measured using western blotting. Angptl2 was found to be elevated in hypertensive rats in vivo and in VSMCs upon Ang II stimulation in vitro. Angptl2 knockdown suppressed cell proliferation, colony formation, cell migration, and invasion as well as the downregulation of Ki67. Additionally, Angptl2 knockdown hindered cell cycle progression and downregulated protein expression of CDK2/4 and cyclin D1, but upregulated p21 expression. Furthermore, Angptl2 knockdown inhibited activation of the NLRP3 inflammasome. Our findings suggest that Angptl2 knockdown suppresses VSMC proliferation, migration, and invasion induced by Ang II. Angptl2 may be a new target for vascular remodeling in hypertension.


Asunto(s)
Angiotensina II , Hipertensión , Proteína 2 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/genética , Proteínas Similares a la Angiopoyetina/metabolismo , Angiotensina II/metabolismo , Angiotensina II/farmacología , Animales , Movimiento Celular , Proliferación Celular , Células Cultivadas , Técnicas de Silenciamiento del Gen , Hipertensión/metabolismo , Antígeno Ki-67/metabolismo , Músculo Liso Vascular/metabolismo , Ratas , Ratas Endogámicas WKY
8.
J Sep Sci ; 45(14): 2446-2457, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35503988

RESUMEN

An herbal prescription is usually composed of several herbal medicines. The complex and diverse components bring great challenges to its bioactivity study. To comprehensively analyze the bioactivity of an herbal prescription, a new strategy based on peak-by-peak cutting and knock-out chromatography was proposed. In this strategy, active compounds were screened out via peak-by-peak cutting from an herbal extract, and the influence of a compound on the overall activity of the herbal extract was evaluated by knock-out chromatography. Qiliqiangxin capsule is an herbal prescription composed of 11 herbal medicines for the treatment of chronic heart failure. A total of 71 peaks were collected through peak-by-peak cutting, and each peak was identified by a high-resolution mass spectrum. The bioassay against 1,1-diphenyl-2-picrylhydrazyl showed that two types of compounds namely salvianolic acids and caffeoylquinic acids were potent scavengers. Knock-out chromatography suggested that the removal of one single compound had no obvious influence on the overall activity of the Qiliqiangxin capsule. After all the main peaks in the Qiliqiangxin capsule were knocked out, the remaining part still exhibited a potent activity, indicating high activity stability of the Qiliqiangxin capsule. The proposed strategy is helpful for the comprehensive analysis of the bioactivity of other herbal prescriptions.


Asunto(s)
Medicamentos Herbarios Chinos , Plantas Medicinales , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Plantas Medicinales/química , Prescripciones
9.
J Asian Nat Prod Res ; 24(1): 59-65, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33511869

RESUMEN

Two new sesquiterpene aryl esters, armimelleolides A and B (1 and 2), and four known ones, were isolated from the EtOAc extract of Armillaria gallica 012 m by column chromatography on silica gel, reversed-phase C18 silica gel and semi-preparative HPLC. Their structures were elucidated on the basis of spectroscopic methods, including extensive 1 D NMR, 2 D NMR and MS. All these compounds showed potential antitumor activities against at least one of the human cancer cell lines (A549, HCT-116, M231 and W256), with IC50 ranging from 2.57 to 19.94 µM.


Asunto(s)
Armillaria , Sesquiterpenos , Ésteres , Estructura Molecular , Sesquiterpenos/farmacología
10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(9): 992-995, 2022 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-36082572

RESUMEN

OBJECTIVE: To carry out clinical and genetic analysis for an infant manifesting perianal lesions, diarrhea and multiple intestinal perforations. METHODS: Genomic DNA of the infant was extracted and subjected to targeted capture exome sequencing. Candidate variants were verified by Sanger sequencing of his family members. RESULTS: The patient was found to harbor c.301C>T and c.188+1G>A compound heterozygous variants of the IL10RA gene, which has suggested the diagnosis of IL10RA-related very early-onset inflammatory bowel disease (VEOIBD). CONCLUSION: The patient was diagnosed with IL10RA-related VEOIBD. The newly discovered c.188+1G>A variant has enriched the spectrum of IL10RA gene variations.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Pruebas Genéticas , Humanos , Lactante , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/patología , Mutación , Secuenciación del Exoma
11.
Cancer Sci ; 110(6): 2014-2021, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31033100

RESUMEN

This study aimed to analyze the association between driver mutations and predictive markers for some anti-tumor agents in non-small cell lung cancer (NSCLC). A cohort of 785 Chinese patients with NSCLC who underwent resection from March 2016 to November 2017 in the First Affiliated Hospital of Guangzhou Medical University was investigated. The specimens were subjected to hybridization capture and sequence of 8 important NSCLC-related driver genes. In addition, the slides were tested for PD-L1, excision repair cross-complementation group 1 (ERCC1), ribonucleotide reductase subunit M1 (RRM1), thymidylate synthase (TS) and ß-tubulin III by immunohistochemical staining. A total of 498 (63.4%) patients had at least 1 driver gene alteration. Wild-type, EGFR rare mutation (mut), ALK fusion (fus), RAS mut, RET fus and MET mut had relatively higher proportions of lower ERCC1 expression. EGFR 19del, EGFR L858R, EGFR rare mut, ALK fus, HER2 mut, ROS1 fus and MET mut were more likely to have TS low expression. Wild-type, EGFR L858R, EGFR rare mut and BRAF mut were associated with lower ß-tubulin III expression. In addition, wild-type, RAS mut, ROS1 fus, BRAF and MET mut had higher proportion of PD-L1 high expression. As a pilot validation, 21 wild-type patients with advanced NSCLC showed better depth of response and response rate to taxanes compared with pemetrexed/gemcitabine (31.2%/60.0% vs 26.6%/45.5%). Our study may aid in selecting the optimal salvage regimen after targeted therapy failure, or the chemo-regimen where targeted therapy has not been a routine option. Further validation is warranted.


Asunto(s)
Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Mutación , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad , Pemetrexed/administración & dosificación , Pronóstico , Taxoides/uso terapéutico , Gemcitabina
12.
Sensors (Basel) ; 19(19)2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31569408

RESUMEN

To perform fast and portable grain moisture measurements under field conditions, a novel moisture sensor was designed, which consisted of a coaxial waveguide, a circular waveguide, and an isolation layer. The electromagnetic characteristics of the sensor were simulated and measured. The analytical model, which represented the relationship between the reflection coefficient of the sensor and the complex permittivity of grain, was established by using the mode matching method. The reflection coefficient of the sensor was measured by using an ultra-wideband (UWB) radar module, and the moisture content of grains was calculated from the complex permittivity by using density-independent model. To verify the performance of the proposed method, wheat, rough rice, and barley were taken as examples. The measured results in the range from 1.0% to 26.0%, wet basis, agreed well with the reference values (R2 was more than 0.99), and the maximum absolute errors for wheat, rough rice, and barley were 1.1%, 1.0%, and 1.4%, respectively. In addition, the effect of isolation layer was discussed. Both the simulation results and the experimental results showed that the isolation layer improved the stability of sensor.

13.
J Asian Nat Prod Res ; 21(4): 316-322, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29338435

RESUMEN

Three new diphenyl ethers (1-3), together with four known isopentylated diphenyl ethers derivatives (4-7), were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed strong inhibitions with inhibition zone diameters (IZD) of 20.2 ± 2.5 mm and 17.9 ± 2.2 mm, respectively. Compound 3 also showed good inhibition with IZD 15.2 ± 1.8 mm. The IZD data of compound 1 is close to that of positive control with IZD 21.9 ± 2.1 mm.


Asunto(s)
Ascomicetos/metabolismo , Endófitos/metabolismo , Fermentación , Éteres Fenílicos/aislamiento & purificación , Éteres Fenílicos/química , Éteres Fenílicos/farmacología
14.
Biochem Biophys Res Commun ; 498(1): 254-261, 2018 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-29337055

RESUMEN

In the present study, we identified a novel circular RNA (circRNA), hsa_circ_0046701, in glioma cells. We measured the expression of hsa_circ_0046701 using qRT-PCR in glioma tissues and cell lines, and explored its functions using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, and Transwell assays. Luciferase reporter assays were performed to validate the correlation between microRNA miR-142-3p and hsa_circ_0046701 or integrin subunit beta 8 (ITGB8). The results showed that hsa_circ_0046701 was significantly upregulated in glioma tissues and cell lines, and knockdown of hsa_circ_0046701 inhibited cell proliferation and invasion. Luciferase reporter assays indicated that hsa_circ_0046701 functions as a sponge for miR-142-3p and regulates the expression of ITGB8. Subsequently, functional assays revealed that silencing of hsa_circ_0046701 could upregulate miR-142-3p, resulting in downregulation of ITGB8. The results demonstrated that the hsa_circ_0046701/miR-142-3p/ITGB8 axis might play critical regulatory roles in the pathogenesis and development of glioma.


Asunto(s)
Neoplasias Encefálicas/genética , Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/patología , Cadenas beta de Integrinas/genética , MicroARNs/genética , ARN/genética , Secuencia de Bases , Neoplasias Encefálicas/patología , Carcinogénesis/patología , Línea Celular Tumoral , Regulación hacia Abajo/genética , Técnicas de Silenciamiento del Gen , Humanos , Cadenas beta de Integrinas/metabolismo , MicroARNs/metabolismo , Invasividad Neoplásica , Oncogenes , ARN/metabolismo , ARN Circular , Regulación hacia Arriba/genética
15.
Chemistry ; 23(69): 17605-17611, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29034523

RESUMEN

Nafion particles doped with ruthenium(II) tris(2,2'-bipyridyl) are synthesized by using a re-precipitation method. Characterization including SEM sizing and quantification of Ru(bpy)32+ in the Nafion particles using UV/Vis spectroscopy was conducted. The synthesized Ru-Nafion particles were investigated electrochemically at both ensemble and single particle levels. Voltammetry of the drop-cast Ru-Nafion particles evidences the successful incorporation of Ru(bpy)32+ into the Nafion particle but only a small fraction of the incorporated Ru(bpy)32+ was detected due at least in part to the formation of the likely agglomerated and irregular "mat" associated with the dropcast technique. In contrast, nano-impact experiments provided a quantitative determination of the amount of Ru(bpy)32+ in single Ru-Nafion particles. Finally, oxidation of solution-phase oxalate mediated by Ru(bpy)32+ within individual Nafion particles was observed, showing the electrocatalytic properties of the Ru-Nafion particles.

16.
Phys Chem Chem Phys ; 20(1): 682-689, 2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-29227481

RESUMEN

Nafion sub-micro particles doped with methyl viologen (MV2+) are synthesized using the re-precipitation method and characterized by scanning electron microscopy and UV-Vis spectroscopy. The electrochemical behavior of MV2+ incorporated into Nafion particles was investigated at both the ensemble and single particle levels. The charge transferred to single MV-Nafion particles was observed using the nano-impact method and shown to be quantitative. Finally, the charge transferred via individual MV-Nafion particle was substantially enhanced in the presence of permanganate. The mechanism of the catalytic nano-impact reaction of mediated permanganate reduction by single MV-Nafion particle is revealed as proceeding via MV+˙ reduced from MV2+ incorporated in Nafion particles through one electron transfer followed by the reduction of permanganate.

17.
Planta Med ; 82(5): 414-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26824624

RESUMEN

Oryzaeins A-D (1-4), four new isocoumarin derivatives, along with five known ones (5-9) were isolated from solid cultures of an endophytic fungus Aspergillus oryzae. Their structures were elucidated by detailed spectroscopic analysis and by comparison with reported data of related derivatives. Among them, compounds 1 and 2 represent the first examples of isocoumarins possessing an unusual 2-oxopropyl group and a rare 3-hydroxypropyl group. Compounds 1 and 2 displayed moderate anti-tobacco mosaic virus activities with inhibition rates of 28.4% and 30.6%, respectively, at the concentration of 20 µM. The new compounds showed moderate inhibitory activities against several human tumor cell lines with IC50 values in the range of 2.8-8.8 µM. Supporting information available online at http://www.thieme-connect.de/products.


Asunto(s)
Antineoplásicos/farmacología , Antivirales/farmacología , Aspergillus oryzae/química , Isocumarinas/farmacología , Virus del Mosaico del Tabaco/efectos de los fármacos , Antibacterianos/farmacología , Antineoplásicos/aislamiento & purificación , Antivirales/aislamiento & purificación , Línea Celular Tumoral , China , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular
18.
Zhongguo Zhong Yao Za Zhi ; 41(1): 92-95, 2016 Jan.
Artículo en Zh | MEDLINE | ID: mdl-28845647

RESUMEN

A new isocoumarin, along with five known ones,were isolated from the fermentation products of an endophytic fungus Aspergillus versicolorby using various chromatographic techniques.Their structures were elucidated on the basis of extensivespectroscopic analysis, including 1D-and 2D-NMR techniques. Compound 1 was evaluated for cytotoxicity against five human tumor cell lines. The results showed that 1 exhibited weak cytotoxicityagainst NB4, SHSY5Y and MCF7 cells with IC50 values of 6.8, 4.3,8.8 µmol•L⁻¹, respectively.


Asunto(s)
Aspergillus/química , Endófitos/química , Isocumarinas/toxicidad , Melanthiaceae/microbiología , Aspergillus/genética , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Endófitos/genética , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Humanos , Isocumarinas/química , Isocumarinas/aislamiento & purificación , Estructura Molecular
19.
Planta Med ; 81(3): 235-40, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25590371

RESUMEN

Versicolactones A-D (1-4), four new butyrolactones, along with four known butyrolactones (5-8) were isolated from the fermentation products of the endophytic fungus Aspergillus versicolor. The structures of compounds 1-4, including absolute configuration, were elucidated by interpretation of the NMR and CD data. Compound 2 was further confirmed by single-crystal X-ray diffraction analysis. In particular, compound 1 is the first naturally occurring butyrolactone possessing an unusual 2-oxopropyl group. More importantly, compounds 1 and 8 displayed significant antitobacco mosaic virus activities with inhibition rates of 46.4 % and 35.4 %, even more potent than the positive control ningnanmycin (30.8 %). Compound 1 also showed moderate cytotoxicity against A549 and MCF7 cells with IC50 values of 3.2 and 2.5 µM, respectively.


Asunto(s)
Antivirales/farmacología , Aspergillus/química , Productos Biológicos/farmacología , Lactonas/farmacología , Sesquiterpenos/farmacología , Virus del Mosaico del Tabaco/efectos de los fármacos , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma del Pulmón , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antivirales/química , Antivirales/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Fermentación , Humanos , Concentración 50 Inhibidora , Lactonas/química , Lactonas/aislamiento & purificación , Lactonas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Células MCF-7 , Estructura Molecular , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/uso terapéutico
20.
J Asian Nat Prod Res ; 17(9): 876-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26411648

RESUMEN

Three new isocoumarins, terrecoumarins A-C (1-3), together with six known isocoumarins (4-9) were isolated from the fermentation products of the fungus Penicillium oxalicum 0403. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. The anti-tobacco mosaic virus (anti-TMV) activities of 1-9 were evaluated. The results revealed that compound 1 showed high anti-TMV activity with inhibition rate 25.4 ± 3.5%. Other compounds also showed weak activity with inhibition rate in the range of 11.3-18.9%.


Asunto(s)
Antivirales/aislamiento & purificación , Antivirales/farmacología , Isocumarinas/aislamiento & purificación , Penicillium/química , Antivirales/química , Fermentación , Isocumarinas/química , Isocumarinas/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Virus del Mosaico del Tabaco/efectos de los fármacos
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