Search results

Filter

Filetype

Your search for "*" yielded 534488 hits

Falsk marknadsföring om hållbart skogsbruk

Dagens svenska skogsbruk är inte ekologiskt hållbart. Att saluföra det som hållbart är därför – för att tala klarspråk – falsk marknadsföring, skriver forskare.

Glucagon-like peptide-1 receptor agonists and diabetic retinopathy : nationwide cohort and Mendelian randomization studies

BACKGROUND: The ability of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) to decrease certain microvascular events has called for the investigation of GLP-1 RAs against diabetic retinopathy (DR), but the evidence is limited. By combining data from observational and Mendelian randomization (MR) studies, we aimed to investigate whether GLP-1 RAs decrease the risk of DR.METHODS: We combined da

Farm and landscape factors interact to affect the supply of pollination services

Farms can harbor substantial biodiversity, which in turn sustains the supply of ecosystem services. The effectiveness of farm management to enhance biodiversity, however, may be modified by land cover in the surrounding landscape beyond a farmer’s direct control. We examined how landscape pattern and farm management affect the abundance and diversity of native bees visiting highbush blueberry in V

Mismatched outcomes for biodiversity and ecosystem services : testing the responses of crop pollinators and wild bee biodiversity to habitat enhancement

Supporting ecosystem services and conserving biodiversity may be compatible goals, but there is concern that service-focused interventions mostly benefit a few common species. We use a spatially replicated, multiyear experiment in four agricultural settings to test if enhancing habitat adjacent to crops increases wild bee diversity and abundance on and off crops. We found that enhanced field edges

Natural hazard threats to pollinators and pollination

Natural hazards are naturally occurring physical events that can impact human welfare both directly and indirectly, via shocks to ecosystems and the services they provide. Animal-mediated pollination is critical for sustaining agricultural economies and biodiversity, yet stands to lose both from present exposure to natural hazards, and future climate-driven shifts in their distribution, frequency,

Mapping connectivity and conservation opportunity on agricultural lands across the conterminous United States

Depending on management practices, agricultural lands can either pose substantial barriers to species movement or can support landscape connectivity by linking areas of high-quality habitat. Balancing connectivity and sustainable food production on agricultural lands is critical to conservation in the conterminous United States (CONUS) where agriculture makes up close to half of total land area. H

Corridors through time : Does resource continuity impact pollinator communities, populations, and individuals?

Spatial aspects of connectivity have received considerable attention from ecologists and conservationists, yet temporal connectivity, the periodic linking of habitats, plays an equally important, but largely overlooked role. Different biological and biophysical attributes of ecosystems underpin temporal connectivity, but here we focus on resource continuity, the uninterrupted availability of forag

Galectin-8 Downmodulates TLR4 Activation and Impairs Bacterial Clearance in a Mouse Model of Pseudomonas aeruginosa Keratitis

Pseudomonas aeruginosa provokes a painful, sight-threatening corneal infection. It progresses rapidly and is difficult to treat. In this study, using a mouse model of P. aeruginosa keratitis, we demonstrate the importance of a carbohydrate-binding protein, galectin-8 (Gal-8), in regulation of the innate immune response. First, using two distinct strains of P. aeruginosa, we established that Gal-8−

The role of Galectin-3 in α-synuclein-induced microglial activation

Background: Parkinson's disease (PD) is the most prevalent neurodegenerative motor disorder. The neuropathology is characterized by intraneuronal protein aggregates of α-synuclein and progressive degeneration of dopaminergic neurons within the substantia nigra. Previous studies have shown that extracellular α-synuclein aggregates can activate microglial cells, induce inflammation and contribute to

Ligand binding and complex formation of galectin-3 is modulated by pH variations

Galectin-3-dependent clusters or lattices are formed at the surface as well as in distinct organelles of eukaryotic cells. Incorporation into membrane proximal networks can fix glycoproteins within subcellular domains or sort them into distinct transport pathways. In the present paper we analysed the effect of acidification on the sugar binding and self-oligomerization of galectin-3. Using a fluor

Bacterial adhesion of Streptococcus suis to host cells and its inhibition by carbohydrate ligands

Streptococcus suis is a Gram-positive bacterium, which causes sepsis and meningitis in pigs and humans. This review examines the role of known S. suis virulence factors in adhesion and S. suis carbohydrate-based adhesion mechanisms, as well as the inhibition of S. suis adhesion by anti-adhesion compounds in in vitro assays. Carbohydrate-binding specificities of S. suis have been identified, and th

A study of the donor properties of sialyl phosphites having an auxiliary 3-(S)-phenylseleno group

Two phosphite sialyl donors, each having an auxiliary 3-(S)-phenylseleno group, were prepared and evaluated. The phenylseleno group was introduced via a new mode of generating phenylselenenic acid (‘PhSeOH’). Although the sialyl donors provided fair yields (32–76%) of the desired sialosides in glycosylations of the reactive acceptor 1,2;3,4-di-O-isopropylidene-α-d-galactopyranose, no sialylated pr

An efficient and convergent route towards water-soluble, chiral and amphiphilic macrocycles

A practical procedure for the synthesis of water-soluble, chiral and amphiphilic macrocyclic molecules is described. Acylation of p-xylylene diamine with Fmoc-protected glycine and aspartic acid, followed by removal of the Fmoc moiety afforded amino acid:p-xylene conjugates as free diamines. These diamines were converted to symmetrical and unsymmetrical macrocycles via stepwise urea formation u

The p-methoxybenzyl ether as an in situ-removable carbohydrate-protecting group : A simple one-pot synthesis of the globotetraose tetrasaccharide

A one-pot synthesis of the globotetraose tetrasaccharide is reported. The synthetic method relies on the use of a p-methoxybenzyl ether as an in situ-removable protecting group. N-Iodosuccinimide/trifluoromethanesulfonic acid-promoted glycosylation of 2-bromoethyl-2,3,6-tri-O-benzoyl-4-O-(2,3,6-tri-O-benzoyl-β-D-galactopyranosyl)-β-D-glucopyranoside 5 at −45 °C with phenyl 2,4,6-tri-O-benzyl-3-O-(

Solid-phase extraction for combinatorial libraries

Solid-phase extraction (SPE) has during the last three years emerged as a convenient method for the purification of compound libraries prepared by solution synthesis. The widespread use of SPE in combinatorial chemistry can be explained by straightforward SPE method development facilitated by the availability of numerous commercial SPE resins. High-speed automated SPE is readily accomplished by ta

Conversion of 2-(trimethylsilyl)ethyl sulfides into thioesters

Treatment of 2-(trimethylsilyl)ethyl sulfides with a carboxylic acid chloride and AgBF4 in CH2Cl2 furnishes the corresponding thioesters in high yields and purities. The conversion of 2-(trimethylsilyl)ethyl sulfides into synthetically versatile thioesters allows such sulfides to be used as sulfhydryl protective groups, since such sulfides are easily prepared and are stable towards many reaction c

Parallel solution synthesis of a 'carbohybrid' library designed to inhibit galactose-binding proteins

Parallel solution S-alkylations of a 1-thio-β-D-galactopyranoside derivative with Michael acceptors and α-chloroketones, followed by ketone reductions, reductive aminations, and acylations were developed to yield a library of 1-thio-β-D-galactopyranosides carrying small and diverse polar- neutral, hydrophobic, aromatic, cationic, or anionic non-carbohydrate aglycon structures. Screening of the lib

Comparative 1H NMR study of hydroxy protons in galabioside and its S-linked 4-thiodisaccharide analogue in aqueous solution

The NMR data obtained from hydroxy protons have been used to investigate the presence and absence of intramolecular hydrogen bonding in aqueous solutions of 2-(trimethylsilyl)ethyl galabioside (α-D-Galp-(1→4)-β-D-Galp-O(CH2)2SiMe3) and the S-linked 4-thiodisaccharide analogue. The data show that there is a weak hydrogen bond interaction between O-6H and O-2'H in galabioside, but not in the thio-an

Solid-phase extraction on C18 silica as a purification strategy in the solution synthesis of a 1-Thio-β-D-galactopyranoside library

A novel strategy for the purification of carbohydrate-based chemical libraries synthesized in solution was developed. Purification of reaction products was accomplished by means of solid-phase extraction enabled by protecting the 2-, 3-, 4-, and 6-hydroxyl groups of a galactose derivative as their hydrophobic O-laurates. The presence of multiple O-laurates allowed adsorption of reaction products o

Immobilization of reducing sugars as toxin binding agents

A simple and economical procedure for the attachment of reducing sugars to aminated solid supports has been developed. Reaction of the amino groups on the solid support with p-nitrophenyl chloroformate, followed by 1,6-hexanediamine, yields a chain-extended amine to which reducing sugars can be attached while remaining accessible to macromolecules. Immobilization of the reducing sugars involves a