Search results for "amer"
showing 10 items of 2105 documents
Stimulator cell-dependent requirement for CD2- and LFA-1-mediated adhesions in T lymphocyte activation by superantigenic toxins.
1992
Abstract The staphylococcal enterotoxins and related microbial T cell mitogens stimulate T cells by cross-linking variable parts of the T cell receptor (TCR) with MHC class II molecules on accessory or target cells. We have used cloned human T cells and defined tumor cells as accessory cells (AC) to study the requirements for T cell activation by these toxins. On AC expressing high levels of CD54 (intercellular adhesion molecule-1, ICAM-1) and CD58 (lymphocyte function-associated antigen-3, LFA-3), mAb to CD2 were relatively ineffective in inhibiting the response to the toxins and antibodies to the lymphocyte function-associated antigen-1 (LFA-1) did not inhibit at all. If added together, h…
Computational approach to design of aptamers to the receptor binding domain of SARS-CoV-2
2021
The aim of the research. In this work, in silico selection of DNA-aptamers to the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein was performed using molecular modeling methods. Material and methods. A new computational approach to aptamer in silico selection is based on a cycle of simulations, including the stages of molecular modeling, molecular docking, molecular dynamic simulations, and quantum chemical calculations. To verify the obtained calculated results flow cytometry, fluorescence polarization, and small-angle X-ray scattering methods were applied. Results. An initial library consisted of 256 16-mer oligonucleotides was modeled. Based on molecular docking results, th…
Functional Fibronectin Adsorption on Aptamer-Doped Chitosan Modulates Cell Morphology by Integrin-Mediated Pathway.
2019
A decisive step in cell-biomaterial interaction is represented by the adsorption of proteins at the interface, whose fine control may be useful to trigger proper cell response. To this purpose, we can selectively control protein adsorption on biomaterials by means of aptamers. Aptamers selected to recognize fibronectin dramatically enhance chitosan ability to promote cell proliferation and adhesion, but the underlying biological mechanism remains unknown. We supposed that aptamers contributed to ameliorate the adsorption of fibronectin in an advantageous geometrical conformation for cells, thus regulating their morphology by the proper activation of the integrin-mediated pathway. We investi…
The selection of aptamers specific for membrane molecular targets
2010
AbstractA growing number of RNA aptamers have been selected experimentally using the SELEX combinatorial approach, and these aptamers have several advantages over monoclonal protein antibodies or peptides with respect to their applications in medicine and nanobiotechnology. Relatively few successful selections have been reported for membrane molecular targets, in contrast to the situation with non-membrane molecular targets. This review compares the procedures and techniques used in selections against membrane proteins and membrane lipids. In the case of membrane proteins, the selections were performed against soluble protein fragments, detergent-membrane protein mixed micelles, whole cells…
Kārļa Ulmaņa režīma organizācija un tiesiskais pamatojums
2016
Šajā darbā tiek pētīta 1934. gada 15. maija valsts apvērsuma rezultātā radušās autoritatīvās valsts pārvaldes formas radītās pārmaiņas, to iespējamā nepieciešamība un tiesiskais pamatojums. Tiek secināts, ka Kārļa Ulmaņa un viņa līdzgaitnieku darbībai apvērsumā nebija tiesiska pamatojuma un tā bija krimināli sodāma saskaņā ar 1933. gada 24. aprīļa Soda likumu. Darba gaitā tiek izdarīti secinājumi par Kārļa Ulmaņa autoritārās varas sekām un to ietekmi uz Latvijas valsti un latviešu tautu, tostarp secinot, ka pēc 1936. gada 16. aprīļa Latvijas tautai vairs nepastāvēja iespēja ietekmēt likumdošanu un tā ir maldināta par tās iespējām ietekmēt likumdošanu, izmantojot Kameru sistēmu. Tiek vērsta …
Micellization and Micellar Structure of a Poly(ethylene oxide)/Poly(propylene oxide)/Poly(ethylene oxide) Triblock Copolymer in Water Solution, As St…
1997
The micellization of the triblock copolymer Pluronic P85 (poly(oxyethylene)27/poly(oxypropylene)39/poly(oxyethylene)27) in aqueous solution was followed vs temperature and addition of aliphatic alcohols, using the spin probe technique. Different types of probes properly chosen (spin-labeled (SL) poly(oxyethylene(4))nonylphenol, SL-Pluronic L62, TEMPO-laurate, TEMPO-hexanoate, CAT 4, CAT 8, CAT 11, CAT 16, and 5-, 7-, 10-, and 12-doxylstearic acids) provided information about the micellar structure (polarity, viscosity, and order degree) at different radial locations. Micellization was found to be low at room temperature, even for 10% aqueous solutions, but strongly increasing with temperatu…
Color degradation mapping of rock art paintings using microfading spectrometry
2021
[EN] Rock art documentation is a complex task that should be carried out in a complete, rigorous and exhaustive way, in order to take particular actions that allow stakeholders to preserve the archaeological sites under constant deterioration. The pigments used in prehistoric paintings present high light sensitivity and rigorous scientific color degradation mapping is not usually undertaken in overall archaeological sites. Microfading spectrometry is a suitable technique for determining the light-stability of pigments found in rock art paintings in a non-destructive way. Spectral data can be transformed into colorimetric information following the recommendations published by the Commission …
CORRELATION BETWEEN SPECTRAL, SEM/EDX AND ELECTROCHEMICAL PROPERTIES OF MAYA BLUE: A CHEMOMETRIC STUDY*
2009
Visible spectra, composition from SEM/EDX and solid-state electrochemical data are correlated for a set of 12 Maya Blue samples from different archaeological sites of Campeche and Yucatan (Mexico). In addition to indigo and dehydroindigo, indirubin and other possibly indigo-type compounds can be detected in Maya Blue samples. Application of hierarchical cluster analysis techniques allows similarity relationships to be established between samples from different sites, confirming prior results which suggest that the preparation of Maya Blue pigment evolved with time during the Maya culture following a ramified scheme.
Exotic insect pests: The impact of the Red Palm Weevil on natural and cultural heritage in Palermo (Italy)
2013
Abstract The impact of invasive exotic pests is increasingly recognised as a global issue. A global strategy to address the exotic pest problem is beginning to evolve, albeit slowly. The International Plant Protection Convention (FAO) has begun the process of harmonizing standards for pest risk analysis to minimise the spread of exotic pests without adversely impacting global trade. However if the impacts of insect invasive species on human health and on agriculture have attracted worldwide attention, researchers and policymakers address directly the connection between invasive species and damage to natural and cultural heritages. The cost of these losses is generally neglected or underesti…
BIOMECHANICAL FACTORS TO BE TAKEN INTO ACCOUNT TO PREVENT INJURIES AND IMPROVE SPORTING PERFORMANCE ON ARTIFICIAL TURF
2009
This article reviews existing knowledge concerning the epidemiology, instruments and regulatory criteria currently used to evaluate artificial turf soccer pitches. Recent years have seen tremendous growth in the use of artificial turf as a playing surface for sports (rugby, soccer, American football…) and the problems traditionally associated with artificial turf and its relationship with a higher percentage of injuries seem to be disappearing. The contribution of biomechanics to the development of new techniques and instruments for analysing the properties and characteristics of grass pitches has contributed towards close collaboration with the regulatory bodies of different sporting organ…