Complement Receptor 1 Is a Sialic Acid-Independent Erythrocyte Receptor of Plasmodium falciparum

Plasmodium falciparum is a highly lethal malaria parasite of humans. A major portion of its life cycle is dedicated to invading and multiplying inside erythrocytes. The molecular mechanisms of erythrocyte invasion are incompletely understood. P. falciparum depends heavily on sialic acid present on glycophorins to invade erythrocytes. However, a significant proportion of laboratory and field isolates are also able to invade erythrocytes in a sialic acid-independent manner. The identity of the erythrocyte sialic acid-independent receptor has been a mystery for decades. We report here that the complement receptor 1 (CR1) is a sialic acid-independent receptor for the invasion of erythrocytes by P. falciparum. We show that soluble CR1 (sCR1) as well as polyclonal and monoclonal antibodies against CR1 inhibit sialic acid-independent invasion in a variety of laboratory strains and wild isolates, and that merozoites interact directly with CR1 on the erythrocyte surface and with sCR1-coated microspheres. Also, the invasion of neuraminidase-treated erythrocytes correlates with the level of CR1 expression. Finally, both sialic acid-independent and dependent strains invade CR1 transgenic mouse erythrocytes preferentially over wild-type erythrocytes but invasion by the latter is more sensitive to neuraminidase. These results suggest that both sialic acid-dependent and independent strains interact with CR1 in the normal red cell during the invasion process. However, only sialic acid-independent strains can do so without the presence of glycophorin sialic acid. Our results close a longstanding and important gap in the understanding of the mechanism of erythrocyte invasion by P. falciparum that will eventually make possible the development of an effective blood stage vaccine

Foreign Banks are Branching out: Changing Geographies of Hungarian Banking, 1987–1999

Walking through the streets of Budapest in spring 1999 could have given you the following impression: the supermarkets (Spar), the milk products sold there (Danone, Müller), and the property markets (OBI) come from different Western European countries such as the Netherlands, France and Germany. Almost all fast food restaurants (McDonalds, Pizza Hut, KFC) and many hotels (Hilton, Mariott) have their origins in the US; shoes and clothes offered in downtown are designed in Italy or France (Benetton, Marco Polo); medicine is predominantly produced in Switzerland (Novartis, Roche) and the banks as well as the car dealerships have their roots everywhere in the so-called Western world - usually including Japan and other Asian countries with major (car) companies - but not in Hungary itself...

Toward a Strategy of Positive Ends

Brigadier General (Retired) Huba Wass de Czege and Lieutenant Colonel Antulio J. Echevarria II make a case for a strategy aimed at achieving positive, rather than neutral or negative, ends. They first discuss the dynamic conditions of the new strategic environment, then explore the options the United States has available for dealing with those conditions. The options include (1) preventive defense, (2) neo-isolationism, and (3) a strategy that pursues positive ends. Only the last, the authors argue, deals with the new security environment in a proactive way. It enables the United States to define its vital interests in terms of conditions--such as peace, freedom, rule of law, and economic prosperity--rather than as the containment or defeat of inimical state or nonstate actors. The basic approach of a strategy of positive ends would be to build and enlarge a circle of stakeholders committed to creating conditions for a profitable and enduring peace--thereby reducing the potential for crises--and to preparing response mechanisms for coping successfully when crises do occur.https://press.armywarcollege.edu/monographs/1104/thumbnail.jp

Toward a Strategy of Positive Ends

Brigadier General (Retired) Huba Wass de Czege and Lieutenant Colonel Antulio J. Echevarria II make a case for a strategy aimed at achieving positive, rather than neutral or negative, ends. They first discuss the dynamic conditions of the new strategic environment, then explore the options the United States has available for dealing with those conditions. The options include (1) preventive defense, (2) neo-isolationism, and (3) a strategy that pursues positive ends. Only the last, the authors argue, deals with the new security environment in a proactive way. It enables the United States to define its vital interests in terms of conditions--such as peace, freedom, rule of law, and economic prosperity--rather than as the containment or defeat of inimical state or nonstate actors. The basic approach of a strategy of positive ends would be to build and enlarge a circle of stakeholders committed to creating conditions for a profitable and enduring peace--thereby reducing the potential for crises--and to preparing response mechanisms for coping successfully when crises do occur.https://press.armywarcollege.edu/monographs/1054/thumbnail.jp