Search results for "LAB"

Bioavailability of antihypertensive lactoferricin B-derived peptides: Transepithelial transport and resistance to intestinal and plasma peptidases

2013

The transepithelial transport of the angiotensin I-converting enzyme (ACE)-inhibitory and antihypertensive lactoferricin B (LfcinB)-derived hexapeptide LfcinB20-25 (RRWQWR) and of its two main fragments RWQ and WQ were investigated using a human intestinal cell (Caco-2) monolayer. The three peptides were susceptible to the action of brush-border peptidases. Intact LfcinB20-25 was not transported across Caco-2 whereas RWQ and WQ were both absorbed through the cell monolayer. Apparent permeability (Papp) values for absorptive transport across the monolayer were 0.7×10-8cms-1 (RWQ) and 3.9×10-8cms-1 (WQ). The effect of pathway-selective inhibitors on peptide absorption suggested paracellular d…

Photoaffinity labeling of the coupling factor 1 from the thermophilic bacterum PS3 by 8-azido ATP

1984

AbstractTo localize the nucleotide binding sites of the F1ATPase (TF1) from the thermophilic bacterium PS3 we have used 14C-labeled 8-azido ATP (8-N3ATP) as photoaffmity label. 8-N3ATP is hydrolyzed by the F,ATPase in the absence of ultraviolet light. Irradiation by ultraviolet light of the enzyme in the presence of 8-N3ATP results in reduction of ATPase activity and in preferential nucleotide specific labeling of the α subunits (0.8–0.9 mol 8-N3ATP/TF1,α:β = 4:1). Inactivation and labeling do not depend on the presence of Mg2+. Both effects decrease upon addition of various nucleotide di- or triphosphates.

Effect of traditional, microwave and industrial cooking on inositol phosphate content in beans, chickpeas and lentils

2003

An high-performance liquid chromatography method for determining inositol phosphate fractions was adapted to legumes. The validity of the method was assessed by estimating the following analytical parameters: linearity (linear response between 125 and 5000 microg inositol hexaphosphate (IP(6))/ml); instrumental precision and method precision (relative standard deviation, %) were 1.9% (IP(6)) for instrumental, and 2.5% (IP(6)) and 8.2% (IP(5)) for method precision. An accuracy was estimated by percentage recovery (72 +/- 3%). The application of this method to raw, conventional, microwave-cooked and ready-to-eat beans, chickpeas and lentils gave IP(6) contents ranging from 0.63 g/100 g dry ma…

Radiolabeling of DOTATOC with the long-lived positron emitter 44Sc.

2010

Abstract The positron-emitting radionuclide 44 Sc with a half-life of 3.97 h and a β + branching of 94.3% is of potential interest for clinical PET. As so far it is available from a 44 Ti/ 44 Sc generator in Mainz, where long-lived 44 Ti decays to no-carrier-added (nca) 44 Sc. The 44 Sc is a trivalent metal cation and should be suitable for complexation with many well established bifunctional chelators conjugated to peptides or other molecular targeting vectors. Thus, the aim of this work was to investigate the potential of 44 Sc for labeling of DOTA-conjugated peptides. DOTA-D-Phe 1 -Tyr 3 -octreotide (DOTATOC) was used as a model molecule to study and optimize labeling procedure. Reaction…

Efficient alkali iodide promoted 18F-fluoroethylations with 2-[18F]fluoroethyl tosylate and 1-bromo-2-[18F]fluoroethane

2003

Abstract Radiochemical 18 F-fluorination yields of several compounds using the secondary labelling precursors 2-[ 18 F]fluoroethyl tosylate ([ 18 F]FETos) and 1-bromo-2-[ 18 F]fluoroethane ([ 18 F]BFE) could be considerably enhanced by the addition of an alkali iodide. The radiochemical yield of [ 18 F]fluoroethyl choline for example could be doubled with [ 18 F]BFE and increased from 13% to ≈80% with [ 18 F]FETos. By addition of alkali iodide to the precursor, the 18 F-fluoroethylation yields of established radiopharmaceuticals, especially in the case of automated syntheses, could be significantly increased without major changes of the reaction conditions.

In vivo analysis of noise dependent activation of white blood cells and microvascular dysfunction in mice

2021

This article contains supporting information on data collection for the research article entitled “Aircraft noise exposure drives the activation of white blood cells and induces microvascular dysfunction in mice” by Eckrich et al. We found that noise-induced stress triggered microvascular dysfunction via involvement of innate immune-derived reactive oxygen species. In this article, we present the instrumentation of mice with dorsal skinfold chambers for in vivo microscopic imaging of blood flow, interaction of leukocytes with the vascular wall (also by fluorescent labelling of blood cells) and vessel diameter. In addition, we explain the preparation of cerebral arterioles for measurement of…

The relationship between food availability and growth in Mytilus galloprovincialis in the open sea (southern Mediterranean)

1998

Abstract With the aim of gathering information about the possibility of culturing mussels ( Mytilus galloprovincialis ) in a south Mediterranean oligotrophic area, different lots of mussels were placed in culture at depths of −5 m and −15 m and their growth monitored on a monthly basis. Temperature and salinity were measured in situ and water samples were collected at different depths each month. Total suspended matter (TSM) and its inorganic (ISM) and organic (OSM) fractions were analysed by gravimetry and loss on ignition. Photosynthetic pigments (chlorophyll- a and phaeopigments), particulate organic carbon (POC) and nitrogen (PON), particulate carbohydrate (CHO), protein (PRT) and lipid…

Determination of soyasaponins I and βg in raw and cooked legumes by solid phase extraction (SPE) coupled to liquid chromatography (LC)-mass spectrome…

2013

Legumes contain a rich variety of phytochemicals as soyasaponins, triterpenoidal glycosides that possess multiple health-promoting properties, such as lowering of cholesterol. In this work, the quantification of soyasaponins I and βg in 60 raw and cooked legumes by using a solid phase extraction (SPE) coupled to a liquid chromatography (LC)-mass spectrometry (MS) method was carried out. Results showed that lentils are a good source of soyasaponins, with a content of soyasaponin I that ranged from 636 to 735 mg kg(-1) and of soyasaponin βg from 672 to 1807 mg kg(-1). The cooking process produced a small loss of soyasaponins in water, that is, 4.8-8.7%, and partially converted soyasaponin βg …

Acetogenins from Annona glabra seeds

1998

Abstract From the cytotoxic ethanol extract of Annona glabra seeds, a new mono-tetrahydrofuranic (mono-THF) acetogenin, glabranin, as well as pair of 22-epimer bis-THF acetogenins, were isolated by semipreparative HPLC. Four known mono-THF acetogenins with an identical threo/trans/threo relative configuration, annonacin, annonacinone, corossolin and corossolone, were found to be potent inhibitors of complex I of the mitochondrial respiratory chain.

1986

In order to graft methacrylonitrile onto preformed networks containing thermolabile azo groups, the monomer was used to swell the networks and then the temperature raised to the decomposition temperature for the azo groups. The unusually high grafting efficiencies yields (e) achieved are explained in terms of both the differences in the reactivities of the primary radicals formed and side reactions, which lead to additional grafting sites. As an aid to understand the dependence of monomer conversion on that of the initiator a kinetic model is discussed, which involves the consideration of the polymerization taking place both in the homogeneous phase and within the polymer pearls, which can …