Search results for "modification"

Biomimetic strategy towards gelatin coatings on PET. Effect of protocol on coating stability and cell-interactive properties

2019

Gelatin-modified poly(ethylene terephthalate) (PET) surfaces have been previously realized via an intermediate dopamine coating procedure that resulted in surfaces with superior haemocompatibility compared to unfunctionalized PET. The present study addresses the biocompatibility assessment of these coated PET surfaces. In this context, the stability of the gelatin coating upon exposure to physiological conditions and its cell-interactive properties were investigated. The proposed gelatin–dopamine-PET surfaces showed an increased protein coating stability up to 24 days and promoted the attachment and spreading of both endothelial cells (ECs) and smooth muscle cells (SMCs). In parallel, physi…

Striving for mutual understanding : native English speakers' views on speech modifications in intercultural encounters

2016

”Foreigner talk” -nimistä ilmiötä on aikaisemmin tutkittu melko laajaltikin eri näkökulmien kautta. Suurin osa tutkimuksesta on tehty 1980-luvulla, jonka jälkeen termin käyttö näyttää hiljalleen vähentyneen. ”Foreigner talk” tarkoittaa muokattua kieltä, jonka tarkoitus on tehdä puheesta ymmärrettävämpää henkilölle, jonka kompetenssi kohdekielessä ei ole toisen puhujan kanssa syystä tai toisesta samalla tasolla: kyseessä voivat olla esimerkiksi kieltä äidinkielenään puhuva henkilö ja kieltä vieraana kielenä puhuva henkilö. Aivan viime aikoina ilmiö näyttää nouseen taas suosioon tutkimuskohteena etenkin osana työympäristöä, jossa kansainväliset kohtaamiset ovat monelle arkipäivää. Siitä huoli…

Cholesterol-Streptolysin O Interaction: An EM Study of Wild-Type and Mutant Streptolysin O

1998

We present transmission electron microscopical data from negatively stained specimens of cholesterol following interaction with the thiol-activated bacterial toxin streptolysin O (SLO) (wild-type and a number of cysteine substitution mutants), with and without chemical modification of the cysteine residues. Two experimental systems were used, one with an aqueous suspension of cholesterol microcrystals and the other with immobilized thin planar cholesterol crystals attached to a carbon film. In both systems the wild-type SLO and two cytolytically active mutants, Cys 530 --Ala (C530A) and Ser 101 --Cys (S101C), readily generated the characteristic SLO arc- and ring-like oligomers on the surfa…

Covalently modified halloysite clay nanotubes: synthesis, properties, biological and medical applications

2017

Halloysite (HNT) is a promising natural nanosized tubular clay mineral that has many important uses in different industrial fields. It is naturally occurring, biocompatible, and available in thousands of tons at low cost. As a consequence of a hollow cavity, HNT is mainly used as nanocontainer for the controlled release of several chemicals. Chemical modification of both surfaces (inner lumen and outer surface) is a strategy to tune the nanotube's properties. Specifically, chemical modification of HNT surfaces generates a nanoarchitecture with targeted affinity through outer surface functionalization and drug transport ability from functionalization of the nanotube lumen. The primary focus …

A NEW ROUTE TO OBTAIN PANI-EAA FLEXIBLE FILMS

2010

Tarkkaavaisuushäiriöiden helpottaminen koulun keinoin : neljä esimerkkiä behavioraalisen intervention toteuttamisesta

2002

Ni@Fe2O3 heterodimers: controlled synthesis and magnetically recyclable catalytic application for dehalogenation reactions

2012

Ni@Fe2O3 heterodimer nanoparticles (NPs) were synthesized by thermal decomposition of organometallic reactants. After functionalization, these Ni@Fe2O3 heterodimers became water soluble. The pristine heterodimeric NPs were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Mossbauer spectroscopy and magnetic susceptibility measurements. A special advantage of the heterodimers lies in the fact that nanodomains of different composition can be used as catalysts for the removal of environmentally hazardous halogenated pollutants.

Synthesis and preliminary in vivo evaluation of well-dispersed biomimetic nanocrystalline apatites labeled with positron emission tomographic imaging…

2015

In recent years, biomimetic synthetic apatite nanoparticles (AP-NPs), having chemical similarity with the mineral phase of bone, have attracted a great interest in nanomedicine as potential drug carriers. To evaluate the therapeutic perspectives of AP-NPs through the mechanisms of action and organs they interact with, the noninvasive monitoring of their in vivo behavior is of paramount importance. To this aim, here the feasibility to radiolabel AP-NPs ("naked" and surface-modified with citrate to reduce their aggregation) with two positron emission tomographic (PET) imaging agents ([F-18]NaF and Ga-68-NO(2)AP(BP)) was investigated. [F-18]NaF was used for the direct incorporation of the radi…

Synthesis and Characterisation of Functionalized borosilicate nanoparticles for boron neutron capture therapy applications

2012

Boron Neutron Capture Therapy (BNCT) is a promising therapy for the cure of diffuse tumors. The successful clinical application of BNCT requires finding new boron-based compounds suitable for an efficient 10B delivery to the cancerous tissues. The purpose of this work is to synthesize borosilicate nanoparticles by a sol–gel recipe, and to functionalize them with folic acid in order to promote their capture by the tumor cells. Whereas sol–gel is a promising technique for the synthesis of nanoparticles, in case of borosilicate systems this approach is affected by significant boron loss during preparation. Here we show that functionalization of borosilicate nanoparticles with folic acid can re…

Fluorination of some highly functionalized cycloalkanes: chemoselectivity and substrate dependence.

2017

A study exploring the chemical behavior of some dihydroxylated β-amino ester stereo- and regioisomers, derived from unsaturated cyclic β-amino acids is described. The nucleophilic fluorinations involving hydroxy–fluorine exchange of some highly functionalized alicyclic diol derivatives have been carried out in view of selective fluorination, investigating substrate dependence, neighboring group assistance and chemodifferentiation.