Search results for "ACID"

Protein tyrosine nitration and thiol oxidation by peroxynitrite-strategies to prevent these oxidative modifications.

2013

The reaction product of nitric oxide and superoxide, peroxynitrite, is a potent biological oxidant. The most important oxidative protein modifications described for peroxynitrite are cysteine-thiol oxidation and tyrosine nitration. We have previously demonstrated that intrinsic heme-thiolate (P450)-dependent enzymatic catalysis increases the nitration of tyrosine 430 in prostacyclin synthase and results in loss of activity which contributes to endothelial dysfunction. We here report the sensitive peroxynitrite-dependent nitration of an over-expressed and partially purified human prostacyclin synthase (3.3 μM) with an EC50 value of 5 μM. Microsomal thiols in these preparations effectively co…

MODIFICATION OF HYDROPHOBIC SURFACE WITH POLYASPARTAMIDE-BASED POLYCATIONS FOR BIOMEDICAL APPLICATION

2013

A convenient way for the achievement of polymer-based solid materials for specific biomedical applications is grafting the appropriate macromolecules onto the surfaces in order to confer them specific properties. To date many approaches have been used to covalently modify polymeric surfaces, and among them chemoselective coupling reactions, usually referred as “click” reactions, gained much attention thanks to simple procedure with high reaction rate under mild reaction conditions (at normal temperature and pressure) [1]. In particular, radical-initiated thiol-yne “photo-click” chemistry has been demonstrated as an effective way to functionalize efficiently surfaces. This method gives also …

CCDC 145029: Experimental Crystal Structure Determination

2001

Related Article: G.Haufe, T.C.Rosen, O.G.J.Meyer, R.Frohlich, K.Rissanen|2002|J.Fluorine Chem.|114|189|doi:10.1016/S0022-1139(02)00040-4

HYALURONIC ACID DERIVATIVE MICELLES AS OCULAR PLATFORMS TO DRUG RELEASE AND CORNEAL PERMEATION

2016

In traditional ocular formulations, only small amount of the administered drug penetrates the cornea to reach the intraocular tissue. One approach to improve the drug ocular bioavailability was to develop colloidal drug delivery systems. Polymeric micelles seem to be very promising for their capacity to dissolve a variety of hydrophobic drugs by enhancing their water solubility and so their bioavailability. They are able to increase ocular drug permeability due to interact with the complex corneal structure. Considering the advantages to use mucoadhesive polymer to increase drug residence time on the ocular surface, the aim of this work was to prepare hyaluronic acid-based micelles as a pla…

Evolutionary advantage conferred by an eukaryote-to-eukaryote gene transfer event in wine yeasts

2015

Although an increasing number of horizontal gene transfers have been reported in eukaryotes, experimental evidence for their adaptive value is lacking. Here, we report the recent transfer of a 158-kb genomic region between Torulaspora microellipsoides and Saccharomyces cerevisiae wine yeasts or closely related strains. This genomic region has undergone several rearrangements in S. cerevisiae strains, including gene loss and gene conversion between two tandemly duplicated FOT genes encoding oligopeptide transporters. We show that FOT genes confer a strong competitive advantage during grape must fermentation by increasing the number and diversity of oligopeptides that yeast can utilize as a s…

Sintesi di complessi metallici e studio della loro interazione con acido desossiribonucleico.

2011

Acid–base properties of functionalised tripodal polyamines and their interaction with nucleotides and nucleic acids

2010

Novel, highly positively charged tripodal polyamines with appended heterocyclic moieties revealed an intriguing panel of protonation species within the biologically relevant range. Studied compounds bind nucleotide monophosphates by mostly electrostatic interactions but only the imidazole analogue showed selectivity toward UMP in respect to other nucleotides. Strong binding of all the studied compounds to both ds-DNA and ds-RNA is to some extent selective toward the latter, showing rather rare RNA over DNA preference.

Hydrogen isotopes (δ2H) of polyunsaturated fatty acids track bioconversion by zooplankton

2022

1. Organisms at the base of aquatic food webs synthesize essential nutrients, such as omega-3 polyunsaturated fatty acids (n-3 PUFA), which are transferred to consumers at higher trophic levels. Many consumers, requiring n-3 long-chain (LC) PUFA, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have limited ability to biosynthesize them from the essential dietary precursor α-linolenic acid (ALA) and thus rely on dietary provision of LC-PUFA. 2. We investigated LC-PUFA metabolism in freshwater zooplankton using stable hydrogen isotopes (δ2H) of fatty acids as tracers. We conducted feeding experiments with the freshwater keystone grazer Daphnia to quantify changes in the δ2…

HPLC/HRMS and GC/MS for Triacylglycerols Characterization of Tuna Fish Oils Obtained from Green Extraction

2023

Background: Fish oil is one of the most common lipidic substances that is consumed as a dietary supplement. The high omega-3 fatty acid content in fish oil is responsible for its numerous health benefits. Fish species such as mackerel, herring, tuna, and salmon are particularly rich in these lipids, which contain two essential omega-3 fatty acids, known as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Objectives: Due to the scarcity of information in the literature, this study aimed to conduct a qualitative and quantitative characterization of triglycerides (TAGs) in crude tuna fish oil using HPLC/HRMS. Fatty acid (FA) determination was also performed using GC/MS. The tuna fis…

In-depth characterization of denitrifier communities across different soil ecosystems in the tundra

2022

Abstract Background In contrast to earlier assumptions, there is now mounting evidence for the role of tundra soils as important sources of the greenhouse gas nitrous oxide (N2O). However, the microorganisms involved in the cycling of N2O in this system remain largely uncharacterized. Since tundra soils are variable sources and sinks of N2O, we aimed at investigating differences in community structure across different soil ecosystems in the tundra. Results We analysed 1.4 Tb of metagenomic data from soils in northern Finland covering a range of ecosystems from dry upland soils to water-logged fens and obtained 796 manually binned and curated metagenome-assembled genomes (MAGs). We then sear…