Search results for " Complement"

The yeast osmosensitive mutant fps1Δ transformed by the cauliflower BobTIP1;1 aquaporin withstand a hypo-osmotic shock

2005

AbstractOsmoregulation plays an important role in cellular responses to osmotic stress in plants and in yeast. Aquaporins contribute to osmotic adjustment by facilitating transport of water or solutes across membranes. The tonoplastic water channel BobTIP1;1 (original name BobTIP26-1) genes are upregulated during dessication stress in cauliflower meristematic tissue. To investigate the physiological importance of BobTIP1;1, we expressed it in a Saccharomyces cerevisiae osmosensitive mutant fps1Δ. We showed that the defect in the yeast glycerol plasma membrane transporter is complemented by a plant cDNA encoding the aquaporin BobTIP1;1 which is localized in the vacuolar membrane of the compl…

Spatial Allocation of European Structural Funds: What Is the Role of Strategic Interactions?

2020

This chapter explores the role of strategic interactions that affect the spatial allocation of structural funds in the European Union. More specifically, this chapter seeks to test if the interactions between government decisions are strategic substitutes or complements in the context of the European structural funds allocation. First, we present a theoretical model which depicts how the strategic interactions could affect the allocation of public grants in a bargaining process. Then, we test the direction of strategic interaction on the allocation of structural funds for the 2000–2006 programming period using spatial econometric techniques. We find a negative spatial interaction between Eu…

Polymorphism in the immunoglobulin-like domains of the receptor tyrosine kinase from the sponge Geodia cydonium.

1996

Sponges [Porifera] are the phylogenetically oldest phylum of the Metazoa. They are provided with both cellular and humoral allorecognition systems. The underlying molecules are not yet known. To study allorecognition in sponges we first determined the frequency of graft rejection in a natural population of the marine sponge Geodia cydonium. We then determined, for the first time at the molecular level, the degree of sequence polymorphism in segments of one molecule which may be related to sponge allorecognition and host defense: the Ig-like domains from the receptor tyrosine kinase [RTK]. Thirty six pairs of auto- and allografts were assayed, either by parabiotic attachment or insertion of …

Suppression of allograft rejection in the sponge Suberites domuncula by FK506 and expression of genes encoding FK506-binding proteins in allografts.

2001

SUMMARY Porifera (sponges) are, evolutionarily, the oldest metazoan phylum. Recent molecular data suggest that these animals possess molecules similar to and homologous with those of the innate and adaptive immune systems of higher Metazoa. Applying the biological system of parabiosis and the technique of differential display of mRNA, two cDNAs encoding putative FK506-binding proteins were isolated. FK506 is successfully used in clinics as a drug to prevent allograft rejection and is toxic to Suberites domuncula cells in vitro at doses above 100ng ml−1. Autograft fusion of transplants from S. domuncula was not affected by FK506. Allograft non-fusion was not affected by FK506 at toxic doses;…

Graphical perception: a case study at the university level

2012

In vitro synthesis of factor B of the alternative pathway of complement activation by mouse peritoneal macrophages

1976

Factor B of the alternative pathway of complement activation was shown to be synthesized and secreted by unstimulated mouse peritoneal macrophages. The activity of B in the culture supernatants from macrophage monolayers was detected by consumption of C3 in reaction mixtures containing supernatant and guinea pig factors C3, D and insoluble C3b. Using a monospecific antiserum, factor B in concentrated culture supernatants was shown by immunodiffusion and immunoelectrophoresis to be identical to factor B in mouse plasma and to form a characteristic complex with cobra venom factor in the presence of D. A steady rate of factor B secretion was observed for 4 days providing the medium was changed…

Digestive vacuole of Plasmodium falciparum released during erythrocyte rupture dually activates complement and coagulation.

2012

Abstract Severe Plasmodium falciparum malaria evolves through the interplay among capillary sequestration of parasitized erythrocytes, deregulated inflammatory responses, and hemostasis dysfunction. After rupture, each parasitized erythrocyte releases not only infective merozoites, but also the digestive vacuole (DV), a membrane-bounded organelle containing the malaria pigment hemozoin. In the present study, we report that the intact organelle, but not isolated hemozoin, dually activates the alternative complement and the intrinsic clotting pathway. Procoagulant activity is destroyed by phospholipase C treatment, indicating a critical role of phospholipid head groups exposed at the DV surfa…

Black Hole Entropy Quantization

2006

Ever since the pioneer works of Bekenstein and Hawking, black hole entropy has been known to have a quantum origin. Furthermore, it has long been argued by Bekenstein that entropy should be quantized in discrete (equidistant) steps given its identification with horizon area in (semi-)classical general relativity and the properties of area as an adiabatic invariant. This lead to the suggestion that black hole area should also be quantized in equidistant steps to account for the discrete black hole entropy. Here we shall show that loop quantum gravity, in which area is {\it not} quantized in equidistant steps can nevertheless be consistent with Bekenstein's equidistant entropy proposal in a s…

Quantum gravity effects near the null black hole singularity

1998

The structure of the Cauchy Horizon singularity of a black hole formed in a generic collapse is studied by means of a renormalization group equation for quantum gravity. It is shown that during the early evolution of the Cauchy Horizon the increase of the mass function is damped when quantum fluctuations of the metric are taken into account.

Origin of metazoan adhesion molecules and adhesion receptors as deduced from cDNA analyses in the marine sponge Geodia cydonium: a review.

1997

The phylogenetic relationships of the kingdom Animalia (Metazoa) have long been questioned. Whether the lowest eukaryotic multicellular organisms, the metazoan phylum Porifera (sponges), independently evolved multicellularity from a separate protist lineage (polyphyly of animals) or whether they were derived from the same protist group as the other animal phyla (monophyly) remains unclear. Analyses of the genes that are typical for multicellularity, e.g. those coding for adhesion molecules (galectin) and adhesion receptors (receptor tyrosine kinase, integrin receptor, receptors featuring scavenger receptor cysteine-rich domains) or elements involved in signal transduction pathways (G-protei…