Search results for "Screen"
showing 10 items of 1374 documents
A New Cacospongionolide Inhibitor of Human Secretory Phospholipase A2 from the Tyrrhenian Sponge Fasciospongia cavernosa and Absolute Configuration o…
1998
A new inhibitor of human secretory phospholipase A2 (PLA2), cacospongionolide E (4a), has been isolated from the Tyrrhenian sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and by chemical transformations. The absolute configuration of cacospongionolides 2a-4a was established using the modified Mosher's method. Cacospongionolide E was the most potent inhibitor toward human synovial PLA2, showing higher potency than the reference compound manoalide and exerting no signs of toxicity on human neutrophils. It showed high activity in the Artemia salina bioassay and moderate toxicity in the fish (Gambusia affinis) lethality assay.
Two new sesquiterpene derivatives from the Tunisian endemic Ferula tunetana Pom.
2010
A new sesquiterpene ester, tunetanin A (1), a new sesquiterpene coumarin, tunetacoumarin A (2), together with eight known compounds, i.e., coladin (3), coladonin (4), isosmarcandin (5), 13-hydroxyfeselol (6), umbelliprenin (7) propiophenone (8), beta-sitosterol (9), and stigmasterol (10), were isolated from the roots of Ferula tunetana. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D- and 2D-NMR experiments and MS analysis, as well as by comparison with published data. The cytotoxicity of compounds 1-7 towards two human colon cancer cell lines, HT-29 and HCT 116, was evaluated. Compounds 3, 4, and 6 showed weak cytotoxic activities.
Unprecedented new nonadecylpara-hydroperoxycinnamate isolated fromErythrina excelsaand its cytotoxic activity
2014
A new unprecedented cinnamate derivative (1) was obtained from Erythrina excelsa (Leguminosae) and identified as nonadecyl para-hydroperoxycinnamate. This compound was isolated together with three known compounds, namely lupeol (2), mixture of sitosterol and stigmasterol (3), and isoneorautenol (4). Their structures were established on the basis of NMR and mass spectroscopic data in conjunction with those reported in the literature. Compound 1 was evaluated for its capability of inhibiting cancer cell lines and growth of a panel of microbial strains. It turned out that 1 is moderately to significantly cytotoxic against six cancer cell lines and shows weak to no antimicrobial activity.
Triterpene Saponins from Tupidanthus calyptratus
2001
Five new bisdesmosidic saponins (1--5) were isolated from the aerial parts of Tupidanthus calyptratus. Their structures were determined by (1)H--(1)H correlation spectroscopy (COSY, TOCSY, ROESY) and (1)H--(13)C correlation (HSQC, HMBC) NMR experiments, FABMS, and chemical data.
Bidentatoside I, a New Triterpene Saponin from Achyranthes bidentata
2001
Bidentatoside I (1) is a new triterpene saponin bearing an unusual dioxopropionic acid unit, isolated from the roots of Achyranthes bidentata. Structural elucidation was performed mainly by chemical and homo- and heteronuclear 2D NMR techniques. This compound did not show any potentiation of the in vitro cytotoxicity of cisplatin in the HT 29 human colon cancer cell line.
Cytotoxic steroidal glycosides from Allium flavum.
2014
Abstract Three new spirostane-type glycosides ( 1 – 3 ) were isolated from the whole plant of Allium flavum . Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as (20 S ,25 R )-2α-hydroxyspirost-5-en-3β-yl O -β- d -xylopyranosyl-(1 → 3)-[β- d -galactopyranosyl-(1→2)]-β- d -galactopyranosyl-(1→4)-β- d -galactopyranoside ( 1 ), (20 S ,25 R )-2α-hydroxyspirost-5-en-3β-yl O -β- d -xylopyranosyl-(1 → 3)-[β- d -glucopyranosyl-(1→2)]-β- d -galactopyranosyl-(1→4)-β- d -galactopyranoside ( 2 ), and (20 S ,25 R )-spirost-5-en-3β-yl O -α- l -rhamnopyranosyl-(1 → 4)-[β- d -glucopyranosyl-(1→2)]-β- d -glucopyranoside ( 3 ). The three saponins were evaluated f…
A magnetic skyrmion as a non-linear resistive element - a potential building block for reservoir computing
2017
Inspired by the human brain, there is a strong effort to find alternative models of information processing capable of imitating the high energy efficiency of neuromorphic information processing. One possible realization of cognitive computing are reservoir computing networks. These networks are built out of non-linear resistive elements which are recursively connected. We propose that a skyrmion network embedded in frustrated magnetic films may provide a suitable physical implementation for reservoir computing applications. The significant key ingredient of such a network is a two-terminal device with non-linear voltage characteristics originating from single-layer magnetoresistive effects,…
Inferring heterozygosity from ancient and low coverage genomes
2016
Abstract While genetic diversity can be quantified accurately from high coverage sequencing data, it is often desirable to obtain such estimates from data with low coverage, either to save costs or because of low DNA quality, as is observed for ancient samples. Here, we introduce a method to accurately infer heterozygosity probabilistically from sequences with average coverage <1× of a single individual. The method relaxes the infinite sites assumption of previous methods, does not require a reference sequence, except for the initial alignment of the sequencing data, and takes into account both variable sequencing errors and potential postmortem damage. It is thus also applicable to …
Genome-Wide Association Study for Incident Myocardial Infarction and Coronary Heart Disease in Prospective Cohort Studies: The CHARGE Consortium
2016
Background Data are limited on genome-wide association studies (GWAS) for incident coronary heart disease (CHD). Moreover, it is not known whether genetic variants identified to date also associate with risk of CHD in a prospective setting. Methods We performed a two-stage GWAS analysis of incident myocardial infarction (MI) and CHD in a total of 64,297 individuals (including 3898 MI cases, 5465 CHD cases). SNPs that passed an arbitrary threshold of 5×10−6 in Stage I were taken to Stage II for further discovery. Furthermore, in an analysis of prognosis, we studied whether known SNPs from former GWAS were associated with total mortality in individuals who experienced MI during follow-up. Res…
A de novo microdeletion of SEMA5A in a boy with autism spectrum disorder and intellectual disability.
2016
AbstractSemaphorins are a large family of secreted and membrane-associated proteins necessary for wiring of the brain. Semaphorin 5A (SEMA5A) acts as a bifunctional guidance cue, exerting both attractive and inhibitory effects on developing axons. Previous studies have suggested that SEMA5A could be a susceptibility gene for autism spectrum disorders (ASDs). We first identified a de novo translocation t(5;22)(p15.3;q11.21) in a patient with ASD and intellectual disability (ID). At the translocation breakpoint on chromosome 5, we observed a 861-kb deletion encompassing the end of the SEMA5A gene. We delineated the breakpoint by NGS and observed that no gene was disrupted on chromosome 22. We…