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showing 10 items of 113 documents
PEGYLATED POLYASPARTAMIDE–POLYLACTIDE BASED NANOPARTICLES PENETRATING CYSTIC FIBROSIS ARTIFICIAL MUCUS
2016
Here, the preparation of mucus-penetrating nanoparticles for pulmonary administration of ibuprofen in patients with cystic fibrosis is described. A fluorescent derivative of α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide is synthesized by derivatization with rhodamine, polylactide, and poly(ethylene glycol), to obtain polyaspartamide− polylactide derivatives with different degrees of pegylation. Starting from these copolymers, fluorescent nanoparticles with different poly(ethylene glycol) content, empty and loaded with ibuprofen, showed spherical shape, colloidal size, slightly negative ζ potential, and biocompatibility toward human bronchial epithelial cells. The high surface poly(ethylene gly…
Anti-proliferative effect of main dietary phytosterols and β-cryptoxanthin alone or combined in human colon cancer Caco-2 cells through cytosolic Ca+…
2015
β-cryptoxanthin (β-Cx) and phytosterols (Ps) have potential against different cancer types, including colon cancer. However, their combined action has not been reported so far. Human colon cancer Caco-2 cells were treated 24 h with β-Cx and/or main dietary Ps (β-sitosterol, campesterol and stigmasterol), alone or in combination, at concentrations compatible with physiological human serum levels. A decrease in cell viability due to apoptosis (rise in sub-G1 population and exposure of membrane phosphatidylserine) was accompanied with dephosphorylation of BAD, mitochondrial depolarization and caspase 3-dependent PARP cleavage, with intracellular Ca2+ influx and increase of RONS levels as initi…
The unsolved relationship of brain aging and late-onset Alzheimer disease.
2009
Late-onset Alzheimer disease is the most common form of dementia and is strongly associated with age. Today, around 24 million people suffer from dementia and with aging of industrial populations this number will significantly increase throughout the next decades. An effective therapy that successfully decelerates or prevents the progressive neurodegeneration does not exist. Histopathologically Alzheimer disease is characterized by extensive extracellular amyloid beta (Abeta) plaques, intracellular neurofibrillary tangles (NFTs), synaptic loss and neuronal cell death in distinct brain regions. The molecular correlation of Abeta or NFTs and development of late-onset Alzheimer disease needs f…
Nanometric ion pair complexes of tobramycin forming microparticles for the treatment of Pseudomonas aeruginosa infections in cystic fibrosis
2019
Abstract Sustained pulmonary delivery of tobramycin from microparticles composed of drug/polymer nanocomplexes offers several advantages against traditional delivery methods. Namely, in patients with cystic fibrosis, microparticle delivery can protect the tobramycin being delivered from strong mucoadhesive interactions, thus avoiding effects on its diffusion toward the infection site. Polymeric ion-pair complexes were obtained starting from two synthetic polyanions, through impregnation of their solid dissociated forms with tobramycin in aqueous solution. The structure of these polymeric systems was characterized, and their activities were examined against various biofilm-forming Pseudomona…
Novel Penicillin-Type Analogues Bearing a Variable Substituted 2-Azetidinone Ring at Position 6: Synthesis and Biological Evaluation
2015
The synthesis and the biological activity of novel semi-synthetic β-lactam compounds containing an azetidinone moiety joined to the amino-nitrogen of the (+)-6-aminopenicillanic acid (6-APA) as new antibacterial agents is reported. The synthesized compounds were screened for their in vitro antimicrobial activity against a panel of Gram positive and Gram negative pathogens and environmental bacteria. Tested compounds displayed good antimicrobial activity against all tested Gram positive bacteria and for Staphylococcus aureus and Staphylococcus epidermidis antimicrobial activity resulted higher than that of the reference antibiotic. Additionally, in vitro cytotoxic screening was also carried …
Effect of β-lactoglobulin (LGB) and k-casein (CSN3) alleles on some characteristics of milk produced by Cinisara cows
2015
It is well known that β-lactoglobulin (LGB) and k-casein (CSN3) alleles affect milk cheese making properties. The purpose of this study was to analyse the A and B allele distribution at the LGB and CSN3 loci in Cinisara breed and their influence on milk and cheese making production traits. The Cinisara is a Sicilian breed which, according to DAD-IS database (FAO), consists of about 5,000 individuals and is reared mainly for milk production which is usually transformed into Caciocavallo Palermitano, a typical stretched-curd cheese. We typed 314 lactating cows at the LGB and CSN3 loci by means of RFLP-PCR analyses. The frequencies of LGB A and B alleles were 0.22 and 0.78, respectively; the f…
Cytoprotection assessment against mycotoxins on HepG2 cells by extracts from Allium sativum L
2021
Abstract Cytoprotection effects of Allium sativum L garlic extract from a local garlic ecotype from Ferrara (Italy) on hepatocarcinoma cells, HepG2 cells, is presented in this study. This garlic type is known as Voghiera garlic and has been characterized as PDO (Protected designation of Origin) product. Voghiera garlic extract (VGE) was evaluated against beauvericin (BEA) and two zearalenone (ZEA) metabolites (α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL))-induced cytotoxicity on HepG2 cells by the MTT (3–4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay, over 24 h and 48 h. Direct treatment, simultaneous treatment and pre-treatment strategies at the dilution 1:16–1:00 for VG…
Syntheses of Four Enantiomers of 2,3-Diendo- and 3-Endo-aminobicyclo[2.2.2]oct-5-ene-2-exo-carboxylic Acid and Their Saturated Analogues
2013
Abstract: Ethyl 2,3- diendo -3-aminobicyclo[2.2.2]oct- 5-ene-2-carboxylate ((±)- 1 ) was resolved with O , O '-dibenzoyltartaric acid via diastere omeric salt formation. The efficient synthesis of the enantiomers of 2,3- diendo -3-aminobicyclo[2.2.2]oct- 5-ene-2-carboxylic acid ((+)- 7 and (–)- 7 ), 3- endo -aminobicyclo[2.2.2]oct-5-ene-2- exo -carboxylic acid ((+)- 5 and (–)- 5 ), cis - and trans -3-aminobicyclo[2.2.2]octa ne-2-carboxylic acid ((+)- 6 , (–)- 6 , (+)- 8 and (–)- 8 ) was achieved via isomerization, hydrogenation and hydrolysis of the corresponding esters (–)- 1 and (+)- 1 . The stereochemistry and relative configurations of the synthesized compounds were determined by NMR sp…
Steric vs. electronic stereocontrol in syndio- or iso-selective ROP of functional chiral β-lactones mediated by achiral yttrium-bisphenolate complexes
2018
International audience; Origins of stereoselectivity in ROP of racemic chiral cyclic esters promoted by achiral yttrium complexes, resulting in the formation of highly heterotactic polylactide, and highly syndiotactic or, more uniquely, highly isotactic poly(3-hydroxybutyrate)s, are discussed. A close interplay between the nature of the cyclic ester, most particularly of the exocyclic functional chain installed on the chiral center of β-lactones, and the ortho-substituents installed on the phenolate rings of the ligand, results in various determining secondary interactions of steric and also electronic nature.
Kopējo augšstilba artēriju hemodinamisko parametru maiņas unilaterālas pēc-oklūzijas hiperēmijas laikā
2016
Pēc pēdējiem literatūras datiem ir zināms, ka pastāv būtiskas atšķirības augšējo un apakšējo ekstremitāšu artēriju reakcijās. Neskatoties uz to, joprojām ir maz pētījumu par hemodinamisko parametru maiņām kāju maģistrālajās artērijās. Īpaši aktuāls ir jautājums par asins plūsmas lineārā ātruma profila komponentiem un to maiņām dažādos apstākļos. Tāpat joprojām nav vienota priekšstata par plūsmas-izraisītās dilatācijas (FMD) reakcijām un to regulācijas mehānismiem kopējās augšstilba artērijās (CFA), kā arī par lokālā stinguma maiņām pēc-oklūzijas reaktīvās hiperēmijas laikā. Darba mērķis ir novērtēt kopējo augšstilba artēriju hemodinamisko parametru maiņas unilaterālas distālas oklūzijas un …