Search results for "ALK"
showing 10 items of 4314 documents
Xanthones and sesquiterpene derivatives from a marine-derived fungus Scopulariopsis sp.
2016
Abstract Two new xanthone derivatives, 12-dimethoxypinselin ( 1 ) and 12- O -acetyl-AGI-B4 ( 2 ), as well as two new phenolic bisabolane-type sesquiterpenes, 11,12-dihydroxysydonic acid ( 15 ) and 1-hydroxyboivinianic acid ( 16 ), together with one new alkaloid, scopulamide ( 21 ) and one new α-pyrone derivative, scopupyrone ( 26 ), in addition to twenty-three known compounds ( 3 – 14 , 17 – 20 , 22 – 25 , 27 – 29 ) were isolated from solid rice cultures of the marine-derived fungus Scopulariopsis sp. obtained from the Red Sea hard coral Stylophora sp. All compounds were unambiguously identified through extensive NMR spectroscopic analyses, and by comparison with the literature. Marfey's re…
Secondary metabolites of the lichen-associated fungus Apiospora montagnei
2017
Abstract The endolichenic fungus Apiospora montagnei isolated from the lichen Cladonia sp. was cultured on solid rice medium, yielding the new diterpenoid libertellenone L (1), the new pyridine alkaloid, 23-O-acetyl-N-hydroxyapiosporamide (2) and the new xanthone derivative 8-hydroxy-3-hydroxymethyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ether (3) together with 19 known compounds (4–22). The structures of the new compounds were elucidated by 1D and 2D NMR spectra as well as by HRESIMS data. The absolute configuration of the new 6,7-seco-libertellenone derivative 1 was determined by single-crystal X-ray diffraction. Four additional known compounds 23–26 were isolated when NaCl or NH4Cl w…
Clinical relevance of antiphospholipid antibodies in primary biliary cirrhosis.
2005
Primary biliary cirrhosis (PBC) is a cholestatic liver disease characterized by the presence of antimitochondrial autoantibodies (AMAs), but also with reactivities to other autoantigens. Recent studies showed that antibodies to phospholipids (APAs) represent an important group of autoantibodies identified in patients with PBC. In this study different types of APAs were identified in the sera of patients with PBC and autoimmune hepatitis (AIH) and control subjects. Sera from patients with PBC and AIH were tested for the presence of antibodies directed against cardiolipin (CL), phosphatidylserine (PS), and to beta(2)-glycoprotein I (beta(2)-GPI). Furthermore, an in-house test for antithrombop…
Long-term response of osteogenic cells on micron and submicron-scale-structured hydrophilic titanium surfaces: sequence of cell proliferation and cel…
2010
Objective: Modifications of surface topography and surface chemistry are key factors for guiding target cells during dental implant healing. Recent in vitro studies confirmed promotion of early osteogenic cell differentiation on submicron scaled surfaces in particular when hydrophilized. However, no long-term observations on both osteogenic cell proliferation as well as on cell maturation have been reported for respectively modified surfaces. Aim of this study was to monitor osteogenic cell proliferation and expression of specific osteogenic cell differentiation markers on a protein level over an extended period of 3 weeks with respect to surface modifications. Material and methods: Modifie…
The geochemistry of Tl and its isotopes during magmatic and hydrothermal processes: The peralkaline Ilimaussaq complex, southwest Greenland
2014
Abstract We use thallium (Tl) concentrations, K/Rb, K/Tl and Rb/Tl ratios and Tl isotopes in minerals from the alkaline to peralkaline Ilimaussaq complex (South Greenland) to trace magmatic differentiation, crustal assimilation, magmatic degassing, ore precipitation and hydrothermal metasomatism. Closed-system magmatic differentiation is marked by a coherent decrease of K/Tl- and K/Rb-ratios, whereas crustal assimilation results in a strong Tl-enrichment, causing low K/Tl-ratios compared to K/Rb-ratios. Thallium isotopes show only slight changes during orthomagmatic differentiation and the assimilation of crustal material cannot be traced, since the isotopic composition of the average crust…
Hydroquinone derivatives from the marine-derived fungus Gliomastix sp.
2017
Eight new hydroquinone derivatives, gliomastins A–D (1–4), 9-O-methylgliomastin C (5), acremonin A 1-O-β-D-glucopyranoside (6), gliomastin E 1-O-β-D-glucopyranoside (7), and 6′-O-acetyl-isohomoarbutin (8), together with seven known analogues were isolated from the marine-derived fungus Gliomastix sp. Their structures were elucidated by extensive spectroscopic analysis including 1D and 2D NMR measurements aided by DFT NMR calculations as well as MS data. TDDFT-ECD and OR calculations were performed to determine the absolute configurations of 1 and the aglycones of 6 and 7. Compound 1 features a novel skeleton, biogenetically derived from a Diels–Alder reaction between derivatives of 11 and 1…
Endothelial cells stimulate osteogenic differentiation of mesenchymal stem cells on calcium phosphate scaffolds
2012
The interaction of mesenchymal stem cells (MSCs) with endothelium in vivo is significant for regenerative processes in organisms. To design concepts for tissue engineering for bone regeneration based on this interaction, the osteogenic differentiation of human bone marrow-derived MSCs in a co-culture with human dermal microvascular endothelial cells (HDMECs) was studied. The experiments were focussed on the regulation of MSCs in a co-culture with HDMECs on different calcium phosphate scaffolds. Alkaline phosphatase (ALP) activity and mRNA expression of various osteogenic markers increased significantly when cells were co-cultured on materials with calcium phosphate scaffolds compared to tis…
Optimization of alkali pretreatment to enhance rice straw conversion to butanol
2021
Abstract The use of rice straw (RS) was enhanced to produce biobutanol as biofuel, for which the NaOH pretreatment was optimized by considering the butanol-biomass ratio that quantify the mass balance efficiency of the three sequential stages of the process: pretreatment, enzymatic hydrolysis and fermentation by Clostridium beijerinckii. The optimum point (solid loading of 5% w/v with 0.75% w/v NaOH at 134 °C for 20 min) of the best cost-wise option yielded an enhanced biomass use of 77.6 g kg RS−1. A maximum butanol titer of 10.1 g L−1 was reached after 72 h of fermentation with the complete uptake of glucose and nearly complete uptake of xylose. The NaOH concentration was the most influen…
Organics in soda-anthraquinone black liquors from hot-water-extracted non-wood feedstocks
2019
The chemical compositions of black liquors (BLs) obtained from the soda-anthraquinone (AQ) pulping of untreated and hot-water-extracted non-wood feedstocks (okra stalk, miscanthus stalk, and wheat straw) were determined. These under-utilized renewable and widely available feedstocks could provide a cheaper source for producing fiber and precursors for manufacturing green chemicals. These BLs were mainly characterized in terms of carbohydrate-derived volatile carboxylic acids (acetic and formic acids) and non-volatile carboxylic acids (hydroxy acids) as well as lignin. Additionally, in each case, the average molar mass and molar mass distribution of the dissolved lignin were measured. Result…
Molecular Virology of Enteric Viruses (with Emphasis on Caliciviruses)
2006
Human caliciviruses are members of the family Caliciviridae and are responsible for a majority of the outbreaks of acute nonbacterial gastroenteritis. In fact, they now are considered a common cause of sporadic cases of diarrhea in the community (Glass et al., 2000b; Koopmans et al., 2002; Lopman et al., 2002; Hutson et al., 2004). These viruses were implicated in as many as 95% of the reported viral gastroenteritis outbreaks examined over a 4.5-year period in the United States (Fankhauser et al., 2002), and similar high incidence rates have been found in other studies (Maguire et al., 1999; Glass et al., 2000b; Koopmans et al., 2000; Lopman et al., 2003). Common features of the Calicivirid…