Search results for "compatibility"
showing 10 items of 859 documents
Effect of polyethelene oxide on the thermal degradation of cellulose biofilm - Low cost material for soft tissue repair in dentistry
2016
Background Bio cellulose is a byproduct of sweet tea fermentation known as kombusha. During the biosynthesis by bacteria cellulose chains are polymerized by enzyme from activated glucose. The single chains are then extruded through the bacterial cell wall. Interestingly, a potential of the Kombucha's byproduct bio cellulose (BC) as biomaterial had come into focus only in the past few decades. The unique physical and mechanical properties such as high purity, an ultrafine and highly crystalline network structure, a superior mechanical strength, flexibility, pronounced permeability to gases and liquids, and an excellent compatibility with living tissue that reinforced by biodegradability, bio…
Gold Nanoparticles Supported on Nanoparticulate Ceria as a Powerful Agent against Intracellular Oxidative Stress
2012
Ceria-supported gold nanoparticles are prepared exhibiting peroxidase activity and acting as radical traps. Au/CeO2 shows a remarkable biocompatibility as demonstrated by measuring cellular viability, proliferation, and lack of apoptosis for two human cell lines (Hep3B and HeLa). The antioxidant activity of Au/CeO2 against reactive oxygen species (ROS) is demonstrated by studying the cellular behavior of Hep3B and HeLa in a model of cellular oxidative stress. It is determined that Au/CeO2 exhibits higher antioxidant activity than glutathione, the main cytosolic antioxidant compound, and its CeO2 carrier. Overall the result presented here shows the potential of implementing well-established …
A new biodegradable and biocompatible hydrogel with polyaminoacid structure
2007
The preparation and physicochemical and biological characterization of a novel polyaminoacid hydrogel have been reported. The ,-poly(N-2- hydroxyethyl)-dl-aspartamide (PHEA) has been used as a starting polymer for a derivatization reaction with methacrylic anhydride (MA) to give rise to the methacrylate derivative named PHM. Photocrosslinking of PHM has been performed in aqueous solution at 313 nm and in the absence of toxic initiators. PHM-based hydrogel has been characterized by scanning electron microscopy, X-ray diffractometry, swelling measurements in aqueous media; the degradation of PHM-based hydrogel has been evaluated as a function of time in the absence or in the presence of ester…
Synthesis and cell surface display of class II determinants by long-term propagated rat T line cells
1987
We have investigated the capacity of the encephalitogenic BS rat T cell line bs 83 and its variant clone bs 83.III.C6 to synthesize and express RT1.B-specific class II molecule subsets defined by monoclonal antibodies (mAb) MRC-OX6 and MRC-OX3. Earlier studies had indicated that mAb MRC-OX6 recognizes three distinct molecular species: an immature oligomeric polypeptide chain complex comprised of the polymorphic subunits alpha, beta and the invariant proteins of the gamma group; a biosynthetic intermediate composed of post-translationally modified alpha, beta and gamma chain (denoted p35) and a fully glycosylated alpha, beta two-chain complex derived from the plasma membrane. MRC-OX3 was sho…
CD8 T Cells Control Cytomegalovirus Latency by Epitope-Specific Sensing of Transcriptional Reactivation
2006
ABSTRACT During murine cytomegalovirus (mCMV) latency in the lungs, most of the viral genomes are transcriptionally silent at the major immediate-early locus, but rare and stochastic episodes of desilencing lead to the expression of IE1 transcripts. This low-frequency but perpetual expression is accompanied by an activation of lung-resident effector-memory CD8 T cells specific for the antigenic peptide 168-YPHFMPTNL-176, which is derivedfrom the IE1 protein. These molecular and immunological findings were combined in the “silencing/desilencing and immune sensing hypothesis” of cytomegalovirus latency and reactivation. This hypothesis proposes that IE1 gene expression proceeds to cell surfac…
Multilayer capsules: a promising microencapsulation system for transplantation of pancreatic islets
2001
In 1980, Lim and Sun introduced a microcapsule coated with an alginate/polylysine complex for encapsulation of pancreatic islets. Characteristic to this type of capsule is, that it consists of a plain membrane which is formed during a single procedural step. With such a simple process it is difficult to obtain instantly a membrane optimized with respect to all the properties requested for islet transplantation. To overcome these difficulties, it is recommended to build up the membrane in several consecutive steps, each optimized for a certain property. In this study, we have analysed such a multilayer microcapsule for the encapsulation of pancreatic islets. Therefore, empty and islet contai…
Expression of Histocompatibility Antigens during the Growth Cycle of Cultured Lymphoid Cells
1974
Histocompatibility antigens are genetically determined markers which are located on plasma membranes of tissue cells of each member of a species. HL-A antigens are the gene products of the major histocompatibility locus in man and represent the human counterparts of the H-2, Ag-B, ChL-A and DL-A systems in mice, rats, chimpanzees and dogs, respectively (Palm, 1964; Snell and Stimpfling, 1966; Rapaport et al., 1970; Balner et al., 1971; Klein and Shreffler, 1971). The great interest in the serologic, genetic, chemical and immunological characterization of histocompatibility antigens is attributable to the fact they provide cell surface markers useful in selecting transplant donors and recipi…
Signals of major histocompatibility complex overdominance in a wild salmonid population
2009
The major histocompatibility complex (MHC) contains the most variable genes in vertebrates, but despite extensive research, the mechanisms maintaining this polymorphism are still unresolved. One hypothesis is that MHC polymorphism is a result of balancing selection operating by overdominance, but convincing evidence for overdominant selection in natural populations has been lacking. We present strong evidence consistent with MHC-specific overdominance in a free-living population of Arctic charr (Salvelinus alpinus) in northernmost Europe. In this population, where just two MHC alleles were observed, MHC heterozygous fish had a lower parasite load, were in better condition (as estimated by a…
Refinements of PIP-Spaces
2009
We have seen in Section 1.5, that the compatibility relation underlying a pip-space may always be coarsened, but not refined in general. There is an exception, however, namely the case of a scale of Hilbert spaces and analogous structures. We shall describe it in this section.
Heat shock protein-peptide complexes for use in vaccines
1996
Abstract The heat shock proteins gp96, HSP70, and HSP90 are complexed to a diverse array of cellular proteins and peptides as a consequence of their chaperone functions. There is good experimental evidence that vaccination with these heat shock protein-peptide complexes elicit immune responses against chaperoned peptide antigens. As shown with gp96, this requires internalization of the heat shock protein-peptide complexes by macrophages and processing of the chaperoned peptides for class I restricted presentation. Via this process, primarily CD8+ antigen-specific T cells are primed by gp96 vaccination. This might represent a general mechanism for priming of MHC-class I restricted T cells by…