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1.
Ann Palliat Med ; 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32434371

RESUMO

In the NCCN guidelines version 1.2019, aromatase inhibitors (AIs) or tamoxifen (TAM) for 5 years plus ovarian function suppression (OFS) were recommended for premenopausal breast cancer patient who has higher risk of recurrence. The meta-analysis established a comparison of the curative effect of two adjuvant endocrine therapies. In order to obtain randomized controlled trials (RCTs) related to this metaanalysis, PubMed and Embase database were searched systematically in English during May 2019. Two reviewers screened the articles and extracted data based on the criteria recommended by the Cochrane collaboration for evaluating evidence in RCTs. The first outcome was disease-free survival (DFS). Overall survival (OS) was the other endpoint. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled utilizing fixed-effect model. The heterogeneity of this study has been described by Cochran's Q and the I2 statistics. Three RCTs which involved 7,203 premenopausal women with breast cancer were available in this meta-analysis. Pooled HRs showed that there was not difference between AIs plus OFS and TAM plus OFS in DFS (HR =0.87, 95% CI: 0.66-1.14, P=0.30). No statistical differences were found in OS between the two adjuvant therapies (HR =1.22, 95% CI: 0.75-1.99, P=0.43). Based on the included studies, there were no statistical differences between AIs plus OFS and TAM plus OFS in DFS and OS.

2.
Int J Syst Evol Microbiol ; 70(1): 11-15, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31560297

RESUMO

Two novel strains (HT111-2T and HT170-2) of the genus Lactobacillus were isolated from Marmota himalayana faecal samples collected on the Qinghai-Tibet Plateau, PR China. The isolates were Gram-stain-positive, rod-shaped, non-spore-forming bacteria with irregular circular colonies. Phylogenetic analysis and comparison of the 16S rRNA gene sequences demonstrated that the two strains form a subcluster and are closest to Lactobacillus hamsteri JCM 6256T (97.3 %) and Lactobacillus amylolyticus DSM 11664T (97.2 %). Phylogenetic analysis of two housekeeping genes (rpoA and pheS) found that strains HT111-2T and HT170-2 had the same closest relatives as the 16S rRNA gene sequence analysis did. The G+C content of strains HT111-2T and HT170-2 were 38.8 mol%. The values of in silico DNA-DNA hybridization with known Lactobacillus species were lower than the threshold (70%). Average nucleotide identity values of strain HT111-2T with L. hamsteri JCM 6256T and L. amylolyticus DSM 11664T were 77.84 % and 76.85 %, respectively. The major fatty acids of strains HT111-2T and HT170-2 were C16 : 0, C18 : 1ω9c and C18 : 0. Results of phenotypic, chemotaxonomic and phylogenetic analyses suggest strains HT111-2T and HT170-2 represent a novel species of the genus Lactobacillus, for which the name Lactobacillus xujianguonis sp. nov. is proposed with HT111-2T (=CGMCC 1.13855T=KCTC 15803T) as the type strain.


Assuntos
Lactobacillus/classificação , Marmota/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Genes Bacterianos , Lactobacillus/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet
3.
Biosens Bioelectron ; 150: 111894, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761484

RESUMO

Multiple mycotoxin contamination has posed health risks in the area of food safety. In this study, co-reduced molybdenum disulfide and gold nanoparticles (rMoS2-Au) were designed and used for the first time as an efficient platform endowing electrochemical electrodes with superior electron transfer rates, large surface areas and strong abilities to firmly couple with large amounts of different aptamers. After further modification with thionine (Thi) and 6-(Ferrocenyl) hexanethiol (FC6S), a platform enabling sensitive, selective and simultaneous determination of two important mycotoxins, zearalenone (ZEN) and fumonisin B1 (FB1), was achieved. The established aptasensor showed excellent linear relationships (R2 > 0.99) when ZEN and FB1 concentrations were in the range of 1 × 10-3-10 ng mL-1 and 1 × 10-3-1 × 102 ng mL-1, respectively. High sensitivity of ZEN and FB1 with a limit of detection as low as 5 × 10-4 ng mL-1 was obtained with excellent selectivity and stability. The effectiveness of the aptasensor was verified in real maize samples, and satisfactory recoveries were attained. The established platform could be easily expanded to other aptamer-based multiplex screening protocols in biochemical research and clinical diagnosis.

4.
Int J Syst Evol Microbiol ; 69(11): 3629-3635, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31511125

RESUMO

Two Gram-stain-positive, irregular rod-shaped (0.2-0.5×1.3-2.5 um) strains, HY056T and HY057, were isolated from the faeces of Equus kiang (the largest of the wild asses) collected at different regions from the Qinghai-Tibetan Plateau of PR China. Phylogenetic analyses indicated that strains HY056T and HY057 belong to the genus Nocardioides by sharing a similarity ranging from 96.3 to 97.0 % in the 16S rRNA gene sequence and forming a distinct cluster with Nocardioides daphniae JCM 16608T, Nocardioides houyundeii 78T, Nocardioides solisilvae Ka25T and Nocardioides gilvus XZ17T. The digital DNA-DNA hybridization value of strain HY056T was 96.9 % with strain HY057, but less than 30.0 % with the above four closest relatives. MK-8(H4) was the predominant (91.6 %) respiratory quinone. The cell wall contained ll-2,6-diaminopimelic acid as the diamino acid of the peptidoglycan. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phospholipid. The predominant fatty acids (>10.0 %) were C18 : 1ω9c and iso-C16:0. The DNA G+C contents of strains HY056T and HY057 were 68.9 and 69.1 mol%, respectively. ß-Glucosidase expression was positive, and acid was produced from d-fructose. Strain HY056T (=CGMCC 4.7563T=JCM 33399T) is assigned as the type strain of a novel species within the genus Nocardioides, for which the name Nocardioidesyefusunii sp. nov is proposed.


Assuntos
Actinobacteria/classificação , Equidae/microbiologia , Fezes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Nat Prod Res ; : 1-6, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31402714

RESUMO

Ustilaginoidin M1 (1), a novel bis-naphtho-γ-pyrone, was isolated from the cultures of the fungus Villosiclava virens which was the pathogen of rice false smut disease. Its structure was elucidated by spectroscopic analysis and by comparison of its physical and spectroscopic data with the literature. Compound 1 was tested for its cytotoxicity against five human cancer cell lines.

6.
Front Chem ; 7: 435, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249829

RESUMO

Ustilaginoidea virens, the causal fungus of rice false smut, was found in previous studies to produce two types of metabolites, ustiloxins and ustilaginoidins. However, genome sequencing of U. virens revealed a plethora of secondary-metabolites-biosynthetic core genes that were capable to biosynthesize unreported metabolites. A large-scale fermentation of U. virens was thus performed, and the fungal extract was chemically re-investigated. After removing the known metabolites, we found a fraction containing unknown phytotoxic substances. Fractionation of this part has led to the isolation of six new sorbicillinoids, namely ustisorbicillinols A~F (1~6), and two new sorbicillinoid-related pyrones, named ustilopyrones A (7) and B (8), together with nine known cogeners (9~17). The structures of the new compounds were elucidated by analysis of their NMR, HRMS, and CD spectra, while ECD, 13C NMR and optical rotation calculations were additionally used for configurational assignments. Plausible biosynthetic pathways for the new compounds were proposed. Phytotoxicity assays revealed that the major sorbicillinoids (12~14, and 16) showed strong inhibition against the radicle and germ elongation of rice and lettuce seeds, with compound 12 displaying the strongest inhibition. The isolated compounds were also evaluated for their cytotoxic, antibacterial, and antifungal activities. Compounds 10, and 12~14 showed moderate cytotoxicities against the tested cell lines with IC50s of 8.83~74.7 µM. Compounds 2, and 10~13 were active against the tested bacteria (MICs 4~128 µg/mL), while compounds 11~13 displayed moderate antifungal activities.

7.
Environ Pollut ; 248: 865-873, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30856502

RESUMO

This study was conducted to investigate mycotoxin exposure in 260 rural residents (age 18-66 years) in Nanjing, China. Paired plasma and first morning urine samples were analyzed for 26 mycotoxin biomarkers, including 12 parent mycotoxins and 14 mycotoxin metabolites, by an ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method. Mycotoxins and their metabolites were detected in 95/260 (36.5%) plasma samples and 144/260 (55.4%) urine samples. The most prevalent mycotoxin in plasma was ochratoxin A (OTA), with the incidence of 27.7% (range 0.312-9.18 µg/L), while aflatoxin B1-lysine (AFB1-lysine) (incidence 19.6%, range 10.5-74.5 pg/mg albumin), fumonisin B1 (FB1) (incidence 2.7%, range 0.305-0.993 µg/L), deoxynivalenol (DON) (incidence 2.3%, range 1.39-5.53 µg/L), zearalenone (ZEN) (incidence 6.5%, range 0.063-0.418 µg/L) and zearalanone (ZAN) (incidence 1.2%, range 0.164-0.346 µg/L) were also detected in plasma samples. Deoxynivalenol-15-glucuronide (DON-15-GlcA) was the most frequently detected urinary mycotoxin, with the incidence of 43.8% (range 0.828-37.7 µg/L). DON (incidence 10.0%, range 1.39-14.7 µg/L), DON-3-glucuronide (DON-3-GlcA) (incidence 15.8%, range 0.583-5.84 µg/L), aflatoxin M1 (AFM1) (incidence 10.4%, range 0.125-0.464 µg/L), ZAN (incidence 7.7%, range 0.106-1.82 µg/L), ZEN (incidence 6.9%, range 0.056-0.311 µg/L), FB1 (incidence 3.1%, range 0.230-1.33 µg/L), T-2 toxin (incidence 2.3%, range 0.248-3.61 µg/L) and OTA (incidence 1.2%, range 0.153-0.557 µg/L) were also found in urine samples. Based on the plasma or urinary levels, the daily intakes of AFB1, FB1, ZEN, DON and OTA were estimated. The results showed that the investigated rural dwellers were exposed to multiple mycotoxins, especially to carcinogenic mycotoxin AFB1 with a mean daily intake of 0.41 µg/kg·bw/day, thereby underlining a potential public health concern. To the best of our knowledge, this is the first study to evaluate human exposure to mycotoxins with direct measurements of multiple mycotoxins in paired plasma and urine samples for over 200 subjects of a single population.


Assuntos
Exposição Dietética/análise , Micotoxinas/sangue , Micotoxinas/urina , Adulto , Biomarcadores/sangue , Biomarcadores/urina , China , Cromatografia Líquida/métodos , Feminino , Contaminação de Alimentos/análise , Humanos , Masculino , População Rural , Fatores Sexuais , Espectrometria de Massas em Tandem/métodos , Adulto Jovem
8.
Anal Chem ; 91(6): 4116-4123, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30793880

RESUMO

An innovative approach based on a surface functional monomer-directing strategy for the construction of a sensitive and selective molecularly imprinted electrochemical sensor for patulin recognition is described. A patulin imprinted platinum nanoparticle (PtNP)-coated poly(thionine) film was grown on a preformed thionine tailed surface of PtNP-nitrogen-doped graphene (NGE) by electropolymerization, which provided high capacity and fast kinetics to uptake patulin molecules. Thionine acted not only as a functional monomer for molecularly imprinted polymer (MIP), but also as a signal indicator. Enhanced sensitivity was obtained by combining the excellent electric conductivity of PtNPs, NGE, and thionine with multisignal amplification. The designed sensor displayed excellent performance for patulin detection over the range of 0.002-2 ng mL-1 (R2 = 0.995) with a detection limit of 0.001 ng mL-1 for patulin. In addition, the resulting sensor showed good stability and high repeatability and selectivity. Furthermore, the feasibility of its applications has also been demonstrated in the analysis of real samples, providing novel tactics for the rational design of MIP-based electrochemical sensors to detect a growing number of deleterious substances.

9.
Sci Rep ; 9(1): 1855, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755627

RESUMO

Ustilaginoidins are a kind of mycotoxins with 9,9'-linked bis-naphtho-γ-pyrones structures produced by the rice false smut pathogen Villosiclava virens. These metabolites displayed a wide range of bioactivities, such as teratogenic, cytotoxic, phytotoxic, and antibacterial activities. So far 26 ustilaginoidins have been isolated from V. virens, among which 18 compounds contained stereogenic center(s), however, most of them were unknown for the absolute configurations, except that of ustilaginoidin D. In this study, the absolute structures of these ustilaginoidins were constructed for the first time by analysis of the biosynthetic monomers obtained from a gene knockout mutant (ΔUV_2091) of V. virens. The gene UV_2091 was predicted to encode an enzyme that dimerized the monomeric naphtho-γ-pyrones in V. virens. Knockout of this gene led to the accumulation of three monomers, namely hemiustilaginoidin F (1), epihemiustilaginoidin D (2), and hemiustilaginoidin D (3), but the production of ustilaginoidins was completely blocked. The structures of the monomers were deduced by spectroscopic analysis, in combination with TDDFT ECD calculations for determining the absolute configurations. These compounds were tested for their phytotoxic, cytotoxic, antibacterial, and antifungal activities. Compounds 1 and 3 showed inhibition against the radicle and plumule elongation of rice and lettuce seeds at the tested concentrations. Compound 1 was active against the tested five human cancer cells, with half maximal inhibitory concentrations (IC50s) of 13.2~37.3 µM. Compounds 1~3 inhibited the growth of the tested pathogenic bacteria with minimum inhibitory concentrations of 8~32 µg/mL, while compound 3 exhibited antifungal activity against Magnaporthe oryzae (IC50, 5.21 µg/mL). A comparison of these data with those of the ustilaginoidins provided insights into the structure-bioactivity relationships.

10.
Crit Rev Food Sci Nutr ; : 1-15, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30806521

RESUMO

Masked mycotoxins are biologically modified phase II metabolites formed by plant defense mechanisms through glucosylation catalyzed by uridine diphosphate -glucosyltransferases. Most of the current reports focus on the occurrence of masked mycotoxins in Europe, America, Africa, and cover other geographic regions, e.g. China and Japan. High proportions of masked mycotoxins co-occurring with their parent forms in various cereal-based food and feedstuff could clearly increase total exposures and pose additional health risks to humans and animals. In contrast to the parent mycotoxins, the data on the toxicity of masked mycotoxins are still scarce, however, the poor existing information showed that masked mycotoxins generally exhibit significant in vitro and in vivo toxicities lower than those of their parent forms, especially for deoxynivalenol-3-glucoside, which is the only thoroughly investigated masked mycotoxin. Although the lower toxicity level of masked mycotoxins, these are probably hydrolyzed into their free forms by intestinal microorganisms in the digestive tract of mammals and thus contribute to unpredicted toxicity. The metabolic characteristics of reported masked mycotoxins are species-specific. The most relevant animal model of human sensitivity, the pig, is most sensitive to masked mycotoxins. This review focuses on updates in the current knowledge on country-specific natural-occurrence data in global surveys, as well as in vitro and in vivo toxicology and metabolic investigations of masked mycotoxins.

11.
Org Lett ; 21(5): 1311-1314, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785293

RESUMO

Ustilobisorbicillinol A (1), which is a novel bisorbicillinoid featuring a unique cage structure that incorporates one sorbicillinol and one sorbyl-containing phenanthrenone unit, was isolated from the culture of Ustilaginoidea virens. Three biogenetically related new metabolites (2-4) were also isolated. Their structures were elucidated by extensive spectroscopic analyses, including the 13C NMR and electronic circular dichroism (ECD) calculations for the configurational assignment. The biosynthetic pathway for these sorbyl-containing polyketides was proposed. Compound 1 showed pronounced cytotoxicity, and it induced significant cell cycle arrest and apoptosis.


Assuntos
Hypocreales/química , Fenantrenos/química , Policetídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Vias Biossintéticas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cicloexanonas/química , Cicloexanonas/farmacologia , Humanos , Estrutura Molecular , Micobioma , Fenantrenos/farmacologia , Policetídeos/farmacologia
12.
Toxins (Basel) ; 11(2)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717237

RESUMO

A simple and reliable analytical method for the simultaneous determination of alternariol (AOH), altenuene (ALT), tentoxin (TEN), altenusin (ALS), tenuazonic acid (TeA), and alternariol monomethyl ether (AME) in grapes was developed by ultra-high-performance liquid chromatography⁻tandem mass spectrometry (UHPLC-MS/MS). A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure with the extraction by acetonitrile and purification by sodium chloride (0.5 g) and anhydrous magnesium sulfate (0.5 g) was established to recover the six Alternaria toxins. After validation by determining the linearity (R² > 0.99), recovery (77.8⁻101.6%), sensitivity (limit of detection in the range of 0.03⁻0.21 µg kg-1, and limit of quantification in the range of 0.09⁻0.48 µg kg-1), and precision (relative standard deviation (RSD) ≤ 12.9%), the analytical method was successfully applied to reveal the contamination state of Alternaria toxins in grapes. Among 56 grape samples, 40 (incidence of 71.4%) were contaminated with Alternaria toxins. TEN was the most frequently found mycotoxin (37.5%), with a concentration range of 0.10⁻1.64 µg kg-1, followed by TeA (28.6%) and AOH (26.8%). ALT (10.7%), AME (3.6%), and ALS (5.4%) were also detected in some samples. To the best of our knowledge, this is the first report about the Alternaria toxins contamination in grapes in China.


Assuntos
Alternaria , Contaminação de Alimentos/análise , Micotoxinas/análise , Vitis/química , China , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
13.
Chem Cent J ; 11(1): 65, 2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29086838

RESUMO

BACKGROUND: Experimental approaches for determining the metabolic properties of the drug candidates are usually expensive, time-consuming and labor intensive. There is a great deal of interest in developing computational methods to accurately and efficiently predict the metabolic decomposition of drug-like molecules, which can provide decisive support and guidance for experimentalists. RESULTS: Here, we developed an integrated, low false positive and reaction types extensive metabolism prediction approach called RD-Metabolizer (Reaction Database-based Metabolizer). RD-Metabolizer firstly employed the detailed reaction SMARTS patterns to encode different metabolism reaction types with the aim of covering larger chemical reaction space. 2D fingerprint similarity calculation model was built to calculate the metabolic probability of each site in a molecule. RDKit was utilized to act on pre-written reaction SMARTS patterns to correct the metabolic ranking of each site in a molecule generated by the 2D fingerprint similarity calculation model as well as generate corresponding structures of metabolites, thus helping to reduce the false positive metabolites. Two test sets were adopted to evaluate the performance of RD-Metabolizer in predicting SOMs and structures of metabolites. The results indicated that RD-Metabolizer was better than or at least as good as several widely used SOMs prediction methods. Besides, the number of false positive metabolites was obviously reduced compared with MetaPrint2D-React. CONCLUSIONS: The accuracy and efficiency of RD-Metabolizer was further illustrated by a metabolism prediction case of AZD9291, which is a mutant-selective EGFR inhibitor. RD-Metabolizer will serve as a useful toolkit for the early metabolic properties assessment of drug-like molecules at the preclinical stage of drug discovery. Graphical abstract A visual example of the metabolic site and the corresponding metabolite of Chloroquine predicted by RD-Metabolizer.

14.
J Agric Food Chem ; 65(25): 5151-5160, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28574707

RESUMO

Ustilaginoidins are a class of bis-naphtho-γ-pyrones, typically produced by Villosiclava virens, the pathogen of the rice false smut (RFS), which has been one of the most destructive rice fungal diseases. Previously, we found that ustilaginoidins identified from the culture of V. virens on rice medium were less polar than those reported from the RFS balls in general. In this study, we reinvestigated the high-performance liquid chromatography with diode array detection and high-resolution mass spectrometry (HPLC-DAD-HRMS) profile of the ethyl acetate (EtOAc) extract of the RFS balls and found several interesting peaks that correspond to new ustilaginoidins. As a result, eight new and polar congeners, named ustilaginoidins Q-T (1-4), 2,3-dihydroustilaginoidin T (5), and ustilaginoidins U-W (6-8), were isolated. In addition, 17 known ustilaginoidins, including ustilaginoidins K-N (9-12), ustilaginoidin P (13), ustilaginoidin E1 (14), isochaetochromin B2 (15), and ustilaginoidins A-J (16-25), were re-isolated. The structures of the new compounds were elucidated by comprehensive analysis of the spectroscopic data. Ustilaginoidins Q (1) and R (2) feature an uncommon 2-hydroxypropyl-substituted skeleton and biogenetically incorporate one more acetate unit than common ustilaginoidins. Ustilaginoidin W (8) is a rare formate-containing bis-naphtho-γ-pyrone. Ustilaginoidins R (2), U (6), B (17), and I (24) showed moderate inhibitory activities toward the radicle or germ elongation of rice seeds. Ustilaginoidins R (2), S (3), V (7), W (8), B (17), C (18), and H-J (23-25) were cytotoxic to the tested human cancer cell lines (HCT116, NCI-H1650, BGC823, Daoy, and HepG2), with IC50 values in the range of 4.06-44.1 µM.


Assuntos
Citotoxinas/toxicidade , Hypocreales/química , Micotoxinas/toxicidade , Oryza/microbiologia , Doenças das Plantas/microbiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Citotoxinas/química , Citotoxinas/isolamento & purificação , Humanos , Hypocreales/fisiologia , Estrutura Molecular , Micotoxinas/química , Micotoxinas/isolamento & purificação
15.
Toxins (Basel) ; 9(3)2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28245594

RESUMO

Rice false smut is a worldwide devastating rice disease infected by the fungal pathogen Villosiclava virens. Ustiloxin A (UA) and ustiloxin B (UB), cyclopeptide mycotoxins, were the major ustiloxins isolated from the rice false smut balls (FSBs) that formed in the pathogen-infected rice spikelets. Based on the specific monoclonal antibodies (mAbs) 2D3G5 and 1B5A10, respectively, against UA and UB, the lateral flow immunoassays (LFIAs) were developed, and the indicator ranges for UA and UB both were 50-100 ng/mL. The cross-reactivities of UB for UA LFIA, and UA for UB LFIA were 5% and 20%, respectively, which were consistent with the icELISA results reported previously. Even at 50,000 ng/mL, none of other commonly existent metabolites in rice samples caused noticeable inhibition. The LFIAs were used for determination of UA and UB contents in rice FSBs and rice grains, and the results were agreeable with those by HPLC and icELISA. There was no change in the sensitivity of either dipstick stored at 4 °C) after at least three months. The developed LFIA has specificity and sensitivity for detecting UA and UB as well as simplicity to use. It will be a potential point-of-care device for rapid evaluation of the rice samples contaminated by UA and UB.


Assuntos
Coloide de Ouro , Imunoensaio/métodos , Micotoxinas/análise , Oryza/química , Peptídeos Cíclicos/análise , Anticorpos Monoclonais/imunologia , Micotoxinas/imunologia , Peptídeos Cíclicos/imunologia
16.
Pest Manag Sci ; 73(7): 1478-1485, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27862895

RESUMO

BACKGROUND: In our search for new agrochemicals from endophytic fungi, the crude extract of the endophytic Hyalodendriella sp. Ponipodef12 associated with the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L. was found to possess larvicidal activity against Aedes aegypti. RESULTS: Fractionation of the extract has led to the isolation of 11 dibenzo-α-pyrones (1-11), including three new congeners: hyalodendriols A-C (1-3). The structures of the new compounds were elucidated by comprehensive spectroscopic analyses, including the modified Mosher's method for the assignment of the absolute configuration. Compounds 2-7 showed potent larvicidal activities against the fourth-instar larvae of A. aegypti with IC50 values ranging from 7.21 to 120.81 µg mL-1 . Among them, penicilliumolide D (6) displayed the strongest activity (IC50 = 7.21 µg mL-1 ). A structure-larvicidal activity relationship was discussed. The possible mode of action of these compounds was assessed for their acetylcholinesterase inhibitory activities. In addition, hyalodendriol C (3) displayed antibacterial activity against Bacillus subtilis and Xanthomonas vesicatoria, and exhibited strong inhibition against the spore germination of Magnaporthe oryzae. CONCLUSION: Our study revealed dibenzo-α-pyrones to be a new class of larvicidal metabolites against A. aegypti. © 2016 Society of Chemical Industry.


Assuntos
Aedes/efeitos dos fármacos , Ascomicetos/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Inseticidas , Pironas/isolamento & purificação , Animais , Antibacterianos/farmacologia , Ascomicetos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Larva/efeitos dos fármacos , Magnaporthe/efeitos dos fármacos , Pironas/química , Pironas/farmacologia , Relação Estrutura-Atividade , Xanthomonas vesicatoria/efeitos dos fármacos
17.
Toxins (Basel) ; 8(9)2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27608042

RESUMO

Ustiloxins are cyclopeptide mycotoxins isolated from rice false smut balls (FSBs), the ball-like colonies transformed from the individual grains through the filament infection by the fungal pathogen Villosiclava virens. There were no obvious relations between ustiloxin content and any of the collection areas, collection times, or average weight of each FSB. The rice false smut balls at early, middle, and late maturity stages were respectively divided into different parts (glume, chlamydospores, mycelia, and pseudoparenchyma). The highest content of ustiloxins A and B of rice FSBs was found at the early maturity stage. Both ustiloxins A and B were mainly distributed in the middle layer containing mycelia and immature chlamydospores of the FSBs. When the rice FSBs were at the early maturity stage, the total yield of ustiloxins A and B in the middle layer of each ball was 48.3 µg, which was 3.20-fold of the yield (15.1 µg) of the inner part of the ball. The rice FSBs at the early maturity stage are the appropriate materials for the production of ustiloxins A and B.


Assuntos
Ascomicetos/metabolismo , Microbiologia de Alimentos , Oryza/microbiologia , Peptídeos Cíclicos/biossíntese , Ascomicetos/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Oryza/crescimento & desenvolvimento , Oryza/metabolismo
18.
Oncotarget ; 7(40): 64967-64976, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27533458

RESUMO

Blocking the interaction of human programmed death 1 (hPD-1) and its ligand hPD-L1 has been a promising immunotherapy in cancer treatment. In this paper, using a computational de novo peptide design method, we designed several hPD-1 binding peptides. The most potent peptide Ar5Y_4 showed a KD value of 1.38 ± 0.39 µM, comparable to the binding affinity of the cognate hPD-L1. A Surface Plasmon Resonance (SPR) competitive binding assay result indicated that Ar5Y_4 could inhibit the interaction of hPD-1/hPD-L1. Moreover, Ar5Y_4 could restore the function of Jurkat T cells which had been suppressed by stimulated HCT116 cells. Peptides described in this paper provide promising biologic candidates for cancer immunotherapy or diagnostics.


Assuntos
Carcinoma/terapia , Imunoterapia/métodos , Peptídeos/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T/imunologia , Antígeno B7-H1/metabolismo , Carcinoma/imunologia , Biologia Computacional , Células HCT116 , Humanos , Células Jurkat , Ativação Linfocitária , Terapia de Alvo Molecular , Peptídeos/síntese química , Receptor de Morte Celular Programada 1/metabolismo , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ressonância de Plasmônio de Superfície , Linfócitos T/efeitos dos fármacos
19.
Molecules ; 21(6)2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27258245

RESUMO

Sorbicillinoids are important hexaketide metabolites derived from fungi. They have a variety of biological activities including cytotoxic, antioxidant, antiviral and antimicrobial activity. The unique structural features of the sorbicillinoids make them attractive candidates for developing new pharmaceutical and agrochemical agents. About 90 sorbicillinoids have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, structures, and biological activities.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/farmacologia , Cicloexanonas/química , Cicloexanonas/farmacologia , Fungos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Produtos Biológicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Cicloexanonas/isolamento & purificação , Humanos , Estrutura Molecular
20.
Toxins (Basel) ; 8(1)2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26771638

RESUMO

Ustilaginoidins are bis-naphtho-γ-pyrone mycotoxins isolated from the rice false smut balls (FSBs) infected by the pathogen Villosiclava virens in rice spikelets on panicles. In order to obtain large amounts of pure ustilaginoidins to further evaluate their biological activities and functions, phytotoxicity on rice, security to human and animals as well as to accelerate their applications as pharmaceuticals, preparative high-speed counter-current chromatography (HSCCC) was successfully applied to the isolation and purification of seven bis-naphtho-γ-pyrone mycotoxins, namely ustilaginoidins A (1), G (2), B (3), H (4), I (5), C (6), and J (7) from the ethyl acetate crude extract of rice FSBs. Both 1 and 2 were prepared by HSCCC from the low-polarity fraction of the crude extract using the two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at the volume ratio of 6.5:3.5:5.0:5.0. Similarly, 3, 4 and 5 were prepared from the medium-polarity fraction using the system at the volume ratio of 4.0:5.0:5.0:6.0, and 6 and 7 were prepared from the higher-polarity fraction using the system at volume ratio of 3.0:5.0:4.0:6.7. A total of 6.2 mg of 1, 5.1 mg of 2, 3.9 mg of 3, 1.2 mg of 4, 5.7 mg of 5, 3.5 mg of 6, and 6.1 mg of 7 with purities of 88%, 82%, 91%, 80%, 92%, 81% and 83%, respectively, were yielded from total 62 mg fraction samples in three independent HSCCC runs. The structures of the purified ustilaginoidins were characterized by means of physicochemical and spectrometric analysis.


Assuntos
Misturas Complexas/química , Hypocreales , Micotoxinas/análise , Doenças das Plantas , Pironas/análise , Cromatografia/métodos , Oryza/microbiologia
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