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1.
Anatol J Cardiol ; 22(3): 117-124, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31475951

RESUMO

OBJECTIVE: A higher visit-to-visit variability in low-density lipoprotein cholesterol (LDL-C) is associated with an increased frequency of cardiovascular events. We investigated the association between the visit-to-visit LDL-C variability and all-cause mortality, myocardial infarction (MI), and coronary revascularization in a population with non-obstructive coronary artery disease (CAD). METHODS: From this retrospective cohort of individuals who underwent coronary angiography from 2006 to 2010, a total of 2.012 consecutive patients with non-obstructive CAD, who underwent three or more LDL-C determinations during the first 2 years, were identified and followed up for 5 years. The variability in the visit-to-visit LDL-C was measured by standard deviation (SD) and coefficient of variation (CV). The risk of all-cause mortality and composite endpoints, MI, and coronary revascularization were evaluated by a multivariable Cox regression analysis. RESULTS: During a 5-year follow-up, a total of 99 (4.92%) mortality cases and 154 (7.65%) cases of composite endpoints were observed. The percentage of subjects who experienced mortality or composite endpoints was higher in those with a higher LDL-C-SD or LDL-C-CV level. The association between the LDL-C variability and clinical endpoints was regardless of possible confounding factors. CONCLUSION: Among the patients with non-obstructive CAD, a higher visit-to-visit LDL-C variability is associated with increasing all-cause mortality or composite endpoints during the long-term follow-up.

2.
J Nat Prod ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478377

RESUMO

Six new sordarin tetracyclic diterpene glycosides, moriniafungins B-G (1-6), and a new sordaricin tetracyclic diterpene, sordaricin B (8), together with two known analogues, moriniafungin (7) and sordaricin (9), were isolated from the zoanthid-derived fungus Curvularia hawaiiensis TA26-15. The structures of the new compounds were elucidated by comprehensive analyses of spectroscopic data, including 1D and 2D NMR and MS data. Compounds 1-6 represent the first case of sordarins from marine-derived fungi possessing a sordarose with a spiro 1,3-dioxolan-4-one ring, which is rare in the nature. Compound 4 showed antifungal activity against Candida albicans ATCC10231 with an MIC value of 2.9 µM.

3.
Rev Sci Instrum ; 90(8): 085002, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472641

RESUMO

The common error calibration model of a linear accelerometer usually cannot meet the accuracy requirement without considering the influence of misalignments in the precision centrifuge test. In order to improve the calibration accuracy, a series of coordinate systems is established and precise accelerations along the input axes of the accelerometers are deduced first. Then, by analyzing the mechanisms of the main error sources, the revised error calibration model is established which includes the misalignments, the radius errors, and the nonlinearity error terms. Then, the measurement methods are proposed to estimate the initial angular misalignments, the installation angular misalignments, and the installation radius misalignments by a theodolite and the accelerometer themselves in the different modes of the centrifuge, respectively. Finally, the experimental measurement results show that the initial angular misalignments are estimated accurately and less than 0.5' after adjustment. Further investigation shows that the adequacy of the common error calibration model decline obviously and the calibration accuracies are lower than 6 × 10-3g/g without considering the misalignments. After compensating for the misalignments in the revised model, the error coefficients are identified precisely, and the calibration accuracies are higher than 1.5 × 10-3g/g.

4.
Mar Drugs ; 17(9)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480589

RESUMO

Identification and analysis of the whole genome of the marine-derived fungus Penicillium brasilianum HBU-136 revealed the presence of an interesting biosynthetic gene cluster (BGC) for non-ribosomal peptide synthetases (NRPS), highly homologous to the BGCs of indole-diketopiperazine derivatives. With the aid of genomic analysis, eight indole-diketopiperazines (1-8), including three new compounds, spirotryprostatin G (1), and cyclotryprostatins F and G (2 and 3), were obtained by large-scale cultivation of the fungal strain HBU-136 using rice medium with 1.0% MgCl2. The absolute configurations of 1-3 were determined by comparison of their experimental electronic circular dichroism (ECD) with calculated ECD spectra. Selective cytotoxicities were observed for compounds 1 and 4 against HL-60 cell line with the IC50 values of 6.0 and 7.9 µM, respectively, whereas 2, 3, and 5 against MCF-7 cell line with the IC50 values of 7.6, 10.8, and 5.1 µM, respectively.

5.
Org Lett ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483134

RESUMO

Although carbon-carbon, carbon-nitrogen, and carbon-oxygen double bonds or their combinations have extensively been applied in phosphine-catalyzed asymmetric cycloaddition, a nitrogen-nitrogen double bond has never been investigated in chiral phosphine catalysis. In this paper, we present phosphine-catalyzed asymmetric [3+2] cycloaddition of diazenes with Morita-Baylis-Hillman (MBH) carbonates to give chiral dihydropyrazoles in high yields with excellent enantioselectivities. Various MBH carbonates and diazenes worked well under the mild reaction conditions.

6.
J Ethnopharmacol ; 244: 112132, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31381954

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Formula Le-Cao-Shi (LCS) is a traditional Chinese medicine (TCM), which has long been used as a folk remedy against hepatitis B in China. The present study was conducted to evaluate the anti-hepatitis B effects of aqueous extract of LCS in vivo and in vitro. MATERIALS AND METHOD: we investigated the anti-HBV effects of LCS in vivo and in vitro with duck hepatitis B model and HepG2.2.15 cell line model, respectively. The serologic and cellular biomarkers and the histopathological changes were examined. RESULTS: By a duck hepatitis B model, the extract of LCS was found to restrain the expressions of duck hepatitis B surface antigen (DHBsAg), hepatitis B e antigen (DHBeAg), and HBV-DNA (DHBV-DNA). Moreover, LCS could decrease the levels of aspartate and alanine aminotransferases (AST and ALT) and ameliorate duck liver histological lesions. Correspondingly, in a HepG2.2.15 cellular model, LCS could also significantly inhibit the secretions of HBsAg and HBeAg. CONCLUSION: LCS exerted potent anti-hepatitis effects against the infection of HBV. The above results demonstrated the first-hand experimental evidences for the anti-hepatitis B efficiency of LCS. Our study provides a basis for further exploration and development of this promising compound prescription to treat hepatitis B disease.

7.
J Nat Prod ; 82(8): 2211-2219, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31373815

RESUMO

Five new tetralones, daldiniones A-E (1-5), three new chromones, 7-hydroxy-5-methoxy-2,3-dimethylchromone (9), 5-methoxy-2-propylchromone (10), and 7-ethyl-8-hydroxy-6-methoxy-2,3-dimethylchromone (11), and two new lactones, helicascolides D and E (16 and 17), together with nine known metabolites (6-8, 12-15, and 18-19) were isolated from the mangrove-derived fungus Daldinia eschscholtzii HJ004. The structures and absolute configurations of the new compounds were determined by analyzing MS and NMR data and utilizing GIAO based 13C NMR chemical shift calculations and quantum chemical electronic circular dichroism (ECD) calculations. Compounds 9, 13, and 18 showed inhibitory activities against α-glucosidase with IC50 values of 13, 15, and 16 µM, respectively.

8.
CNS Neurosci Ther ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31411808

RESUMO

INTRODUCTION: The occurrence of circadian rhythm disorder in patients with Alzheimer's disease (AD) is closely related to the abnormal deposition of amyloid-ß (Aß), and d-Ser2-oxyntomodulin (Oxy) is a protease-resistant oxyntomodulin analogue that has been shown to exert neuroprotective effects. AIMS: This study aimed to explore whether Oxy, a new GLP-1R/GCGR dual receptor agonist, can improve the Aß-induced disrupted circadian rhythm and the role of GLP-1R. METHODS: A mouse wheel-running experiment was performed to explore the circadian rhythm, and western blotting and real-time PCR were performed to assess the expression of the circadian clock genes Bmal1 and Per2. Furthermore, a lentivirus encoding an shGLP-1R-GFP-PURO was used to interfere with GLP-1R gene expression and so explore the role of GLP-1R. RESULTS: The present study has confirmed that Oxy could restore Aß31-35-induced circadian rhythm disorders and improve the abnormal expression of Bmal1 and Per2. After interfering the GLP-1R gene, we found that Oxy could not improve the Aß31-35-induced circadian rhythm disorder and abnormal expression of clock genes. CONCLUSION: This study demonstrated that Oxy could improve Aß31-35-induced circadian rhythm disorders, and GLP-1R plays a critical role. This study thus describes a novel target that may be potentially used in the treatment of AD.

9.
Ecotoxicol Environ Saf ; 183: 109516, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31394375

RESUMO

The triclosan (TCS) is one of the most commonly detected organic pollutants in the sewage sludge. TCS could induce phytotoxicity in plants. Salicylic acid (SA) is a phenolic compound capable of enhancing plant growth and development. It is well documented that abiotic stress tolerance could be enhanced by exogenous application of SA. However, the regulatory mechanisms for functions of endogenous SA in plants' responses to xenobiotics stress remains unclear. Our results indicated that TCS suppressed plant growth by restricting photosynthesis, decreasing chlorophyll contents and inducing over production of reactive oxygen species (ROS). Interestingly, SA or glutathione (GSH) application could significantly improve plant tolerance to TCS. Moreover, endogenous SA and the expression of a SA binding protein 2 (SABP2) gene were found to be elevated in tobacco under TCS treatment. The overexpression of LcSABP, a SABP2-like gene cloned from the leaves of Lycium chinense, markedly enhanced the SA content in the transgenic plants under TCS stress. The LcSABP-overexpressing plants presented higher photosynthesis rate, chlorophyll content, glutathione reductase (GR) and glutathione-S-transferase (GST) enzymes activities, GSH content and lower O2-•, H2O2 and malondialdehyde (MDA) content in comparison with WT tobacco with TCS treatment. One of the GSH synthesis-related gene, NtGSHS, also showed higher expression level in the transgenic tobacco in comparison with control plants with TCS stress treatment. These results indicated that SABP2 played a positive regulatory role in plant response to TCS stress via increasing the endogenous SA levels. The increased SA content might then increase the GSH content, probably through an increase in GR activity and GSHS gene expression, thus inducing the antioxidant and xenobiotics detoxification systems, which promoted TCS stress tolerance in tobacco plants.

10.
J Hazard Mater ; 381: 120967, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31421551

RESUMO

Except for the dangerous Boliden-Norzink technology, recovering gaseous Hg0 as liquid Hg0 using recyclable sorbents was an achievable method to control Hg0 emissions from smelting flue gas. In this study, Ti was incorporated into sulfurated γ-Fe2O3 to improve its performance for capturing Hg0 from smelting flue gas, and the mechanism of Ti incorporation on Hg0 adsorption onto sulfurated γ-Fe2O3 was investigated by comparing the kinetic parameters. The kinetic analysis showed that the Hg0 adsorption rate primarily depended on the amounts of surface adsorption sites for the physical adsorption of Hg0 and surface S22- for Hg0 oxidation. Since the amounts of both adsorption sites and S22- on sulfurated γ-Fe2O3 increased remarkably after Ti incorporation, Hg0 adsorption onto sulfurated γ-Fe2O3 was notably improved by 190-350%. The capacity of sulfurated Fe-Ti spinel for Hg0 capture could reach 48.6 mg g-1 and its average adsorption rate could reach 43.3 µg g-1 min-1 in 3 h. Meanwhile, the used sulfurated Fe-Ti spinel could be easily regenerated without any apparent degradation. Thus, sulfurated Fe-Ti spinel offered a significant advantage in recovering Hg0 from smelting flue gas.

11.
Sci Total Environ ; 694: 133494, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31398650

RESUMO

Volatile organic compounds (VOCs) in drinking water may potentially be hazardous. We developed a novel non-targeted analysis method of VOCs in drinking water that uses dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry. Analysis parameters were selected from range-finding tests on the peak number and average area of the extracted compounds. The optimized method was applied to analyze VOCs in tap water samples collected from Wuhan City, China. Twenty-seven compounds with high match degrees and a high prevalence were selected for quantification and evaluation. We used structure-activity relationships to predict the carcinogenicity of these compounds. Although most of the compounds were non-toxic, compounds such as dibutyl phthalate and diacetone alcohol should be investigated further. Untargeted analysis of the tap water samples identified 75-200 VOCs, including 67 highly prevalent compounds. Industrial and pharmaceutical chemicals accounted for approximately 70% of the VOCs in the samples. This method of non-targeted analysis and in silico toxicity prediction is simple and economic, and could be used in screening VOCs in drinking water.

12.
Sci Total Environ ; 694: 133698, 2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31401504

RESUMO

Human behavior is affected not only by individuals' own psychological factors but also by the surrounding environment and the behaviors of others. Existing studies on tourists' responsible environmental behaviors tend to focus only on tourists' own psychological and environmental factors while ignoring the referential role of other people's behavior. The behavioral reference of others in tourist destinations is an important situational factor that affects tourists' responsible environmental behaviors and has important research value. Based on the theory of planned behavior and taking the Zhongshan Mausoleum Scenic Area as an example, this paper explores the influence of other people's behavioral reference on tourists' responsible environmental behaviors by using the multi-group analysis method of structural equation modelling. The results show the following: (1) Tourists' attitudes toward environmental behavior and subjective norms have a significant positive impact on their responsible environmental behavioral intention, perceived behavioral control has a significant positive impact on their responsible environmental behavioral intention and their responsible environmental behaviors, and responsible environmental behavioral intention has a significant positive impact on responsible environmental behaviors. (2) Tourist destination behavioral reference plays a positive regulatory role in the relationship between tourists' responsible environmental behavioral intention and responsible environmental behaviors. Accordingly, this paper proposes relevant countermeasures and suggestions for the high-quality management and development of tourist destinations.

14.
Biomed Pharmacother ; 117: 109190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387170

RESUMO

Le-Cao-Shi (LCS), a formula of Traditional Chinese Medicine (TCM), has been used as a folk medicine for protection and treatment of liver injury. However, scientific evidences on its hepatoprotective effects have not been investigated. In this study, hepatoprotective activities of LCS water extracts (LCS-W) and ethanol extracts (LCS-E) against carbon tetrachloride (CCl4)-induced liver damage were investigated in vivo and in vitro. In vivo experiments, pretreatment of LCS-W and LCS-E to rats significantly declined the levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and markedly increased the activity of superoxide dismutase (SOD) and ameliorated the level of malondialdehyde (MDA) induced by CCl4 treatment. Especially, LCS-WM group significantly prevented the elevation of lipid peroxidation level induced by CCl4, with the MDA level closed to that of normal group. Histopathological examinations further confirmed that LCS-W and LCS-E could protect the liver cells from CCl4-induced damage. In addition, immunohistochemically analysis revealed that LCS-W could significantly down-regulated the hepatic protein expression of necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). Correspondingly, LCS-W and LCS-E were observed to promote cell viability and decline the levels of ALT, AST, and lactate dehydrogenase (LDH) in vitro. It could be concluded that LCS can exert a protective effect against CCl4-induced hepatotoxicity, which might be a potential therapeutic prescription for preventing or treating liver injury. Notably, LCS-W displayed better hepatoprotective activity against CCl4-induced injury than that of LCS-E, suggesting that LCS extracted by water decoction has good development prospects. Our results contribute towards the validation of the traditional use of LCS in the treatment of liver disorders.

15.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2667-2674, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418191

RESUMO

With a greenhouse pot experiment, we investigated the effects of nitrogen (N) and plant growth promoter (brassinolide, BR) addition on the growth and competitive ability of three common plant species of typical steppe in Inner Mongolia, including Leymus chinensis, Astragalus adsurgens and Stipa krylovii. We added N at rates of 0, 0.1, 0.2, 0.4, 0.8 mg·g-1 soil and BR at rates of 0 and 0.005 mg·g-1 soil during plant growth in monoculture or with L. chinensis being planted in mixing with other two species, respectively. There were significant effects on biomass of L. chinensis and A. adsurgens, but not on that of S. krylovii with increase of N and BR addition. The effects of N addition on the growth of L. chinensis varied with accompanying plant species. Nitrogen addition increased aboveground biomass production of L. chinensis when growing in monoculture and mixed with A. adsurgens, but decreased its belowground biomass when growing mixed with S. krylovii. With increasing soil N availability, plant biomass allocation of L. chinensis showed significant decrease in root-shoot ratio when it was in monoculture or mixed with S. krylovii, but similar changes were not found when it was planted in mixing with A. adsurgens. The significant effects of BR addition on plant growth appeared occasionally. BR addition significantly reduced belowground biomass of A. adsurgens in its monoculture and significantly increased aboveground biomass of L. chinensis when it was planted in mixing with A. adsurgens. The results indicated that the appropria-tely combined addition of N and BR could effectively enhance biomass production of specific species combinations in grasslands, which has application prospects in the restoration of degraded grassland.

16.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2845-2853, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418211

RESUMO

The safety of feed derived from genetically modified (GM) crops is one of the focuses of attention. To evaluate the ecotoxicological effects of transgenic mCry1Ac maize (BT799) on fish, zebrafish (Danio rerio) were fed extruded feeds containing either 20% GM maize (GMF) or its parental control maize (PF), GM maize meal (GMM) or its parental control maize meal (PMM), and a control commercial feed (CF), respectively. The growth performance, histopathology, reproduction, antioxidant enzyme activity and mRNA expression levels of sensitive protein in the liver were investigated over the course of a 98-day feeding trial. The results showed that transgenic mCry1Ac maize had no significant effect on growth, histopathology of the liver, brain and intestinal tract, fecundity, hatching rate of fertilized eggs, superoxide dismutase (SOD), catalase (CAT) activity, mRNA expression levels of SOD and CAT, or heat shock protein 70 (HSP70) and vitellogenin (VTG) in the liver. However, zebrafish fed the commercial feed exhibited significantly greater weight, longer length, and higher specific growth rate than those fed feeds (GMF and PF) and maize meals (GMM and PMM). The hatching rate of zebrafish in the feed groups was significantly lower than that of the maize meal groups and the commercial feed group. The mRNA transcriptional levels of VTG were significantly higher in the liver for the feed groups (3.85±0.76) than that for the maize meal groups (1.60±0.56). These results suggest that transgenic mCry1Ac maize has no ecotoxicological effects on zebrafish. However, the differences in nutrient composition and palatability between the extruded experimental feeds and the commercial feed would lead to significant diffe-rences in some parameters.

17.
Acta Biomater ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31401346

RESUMO

In the present study, a novel biodegradable Zn-0.8Cu coronary artery stent was fabricated and implanted into porcine coronary arteries for up to 24 months. Micro-CT analysis showed that the implanted stent was able to maintain structural integrity after 6 months, while its disintegration occurred after 9 months of implantation. After 24 months of implantation, approximately 28 ±â€¯13 vol% of the stent remained. Optical coherence tomography and histological analysis showed that the endothelialization process could be completed within the first month after implantation, and no inflammation responses or thrombosis formation was observed within 24 months. Cross-section analysis indicated that the subsequent degradation products had been removed in the abluminal direction, guaranteeing that the strut could be replaced by normal tissue without the risk of contaminating the circulatory system, causing neither thrombosis nor inflammation response. The present work demonstrates that the Zn-0.8Cu stent has provided sufficient structural supporting and exhibited an appropriate degradation rate during 24 months of implantation without degradation product accumulation, thrombosis, or inflammation response. The results indicate that the Zn-0.8Cu coronary artery stent is promising for further clinical applications. STATEMENT OF SIGNIFICANCE: Although Zn and its alloys have been considered to be potential candidates of biodegradable metals for vascular stent use, by far, no Zn-based stent with appropriate medical device performance has been reported because of the low mechanical properties of zinc. The present work presents promising results of a Zn-Cu biodegradable vascular stent in porcine coronary arteries. The Zn-Cu stent fabricated in this work demonstrated adequate medical device performance both in vitro and in vivo and degraded at a proper rate without safety problems induced. Furthermore, large animal models have more cardiovascular similarities as humans. Results of this study may provide further information of the Zn-based stents for translational medicine research.

18.
Accid Anal Prev ; 132: 105260, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31442924

RESUMO

Car-following is a common driving behavior which has a significant effect on driver safety and comfort. Although a large number of studies have focused on car-following models for autonomous vehicles (AV) and connected vehicles (CV), car-following models for AV and CV which consider cut-ins in mixed traffic have not been investigated. In this study, a human-like car-following model for AV and CV was developed by examining the effect of cut-in vehicles on car-following behavior and the expectations of drivers. The cut-in position, reaction time, acceleration, and desired distance were investigated on a real freeway in an instrumented vehicle. Corresponding to results from previous studies, the cut-in vehicles maintain a safe distance from the preceding vehicle and a larger distance from the following vehicle to avoid conflict. Analysis of the behavior of the following driver illustrates that in the keeping stages, the reaction time after the cut-in is 0.85 s for the acceleration stimulus and 0.70 s for the deceleration stimulus. These times are shorter than the response time before the cut-in for the acceleration (1.95 s) and deceleration stimuli (1.66 s). The acceleration, rate of increase in the acceleration with the relative speed, and the desired distance are lower after than before the cut-in events. In this paper, a human-like car-following model for cut-in situations is proposed, which is designed for autonomous vehicles. Unlike previous car-following models, the proposed model has a shorter response time and lower deceleration in cut-in situations. The proposed model may help to improve car-following safety, driver comfort, and trust in AVs and CVs.

19.
Chem Commun (Camb) ; 55(70): 10464-10467, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31411218

RESUMO

In this communication, a chiral squaramide-catalyzed asymmetric dearomative tandem annulation reaction of unmodified Morita-Baylis-Hillman alcohols with azomethine imines has been achieved through a kinetic resolution of MBH alcohols under mild conditions, giving pharmaceutically interesting functionalized hetero-bicyclo[3.3.1]nonane derivatives in good to excellent yields with excellent enantioselectivities.

20.
Pak J Pharm Sci ; 32(3): 1103-1105, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31278726

RESUMO

Invasive fungal infections caused by Candida albicans constitute a prevalent worldwide health problem. Due to limited antifungal agents available, more efforts have been made towards searching the novel anti-candida drugs with low cytotoxicity. The present study was aimed to investigate the antifungal activities of baicalin and/or sodium bicarbonate (SB) against 29 C. albicans isolates including 27 clinical ones. By using broth microdilution method and checkerboard assay, it was observed that the minimum inhibitory concentrations (MICs) of baicalin and SB alone were > 2048 µg/mL, and those of baicalin and SB in combination decreased 16-32 folds with fractional inhibitory concentration index (FICI) in a range of 0.094-0.375. The results presented the strong synergism between SB and baicalin in 27 clinical C. albicans isolates and provided an alternative choice against C. albicans.

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