There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

J. Appl. Cryst.の発刊に際して

The Huisgen 1,3-dipolar cycloaddition reaction of organic azides and alkynes has gained considerable attention in recent years due to the introduction in 2001 of Cu(1) catalysis by Tornoe and Meldal, leading to a major improvement in both rate and regioselectivity of the reaction, as realized independently by the Meldal and the Sharpless laboratories. The great success of the Cu(1) catalyzed reaction is rooted in the fact that it is a virtually quantitative, very robust, insensitive, general, and orthogonal ligation reaction, suitable for even biomolecular ligation and in vivo tagging or as a polymerization reaction for synthesis of long linear polymers. The triazole formed is essentially chemically inert to reactive conditions, e.g. oxidation, reduction, and hydrolysis, and has an intermediate polarity with a dipolar moment of ∼5 D. The basis for the unique properties and rate enhancement for triazole formation under Cu(1) catalysis should be found in the high ∆G of the reaction in combination with the low character of polarity of the dipole of the noncatalyzed thermal reaction, which leads to a considerable activation barrier. In order to understand the reaction in detail, it therefore seems important to spend a moment to consider the structural and mechanistic aspects of the catalysis. The reaction is quite insensitive to reaction conditions as long as Cu(1) is present and may be performed in an aqueous or organic environment both in solution and on solid support.

Cu-catalyzed azide-alkyne cycloaddition.

Macrophages are innate immune cells with well-established roles in the primary response to pathogens, but also in tissue homeostasis, coordination of the adaptive immune response, inflammation, resolution, and repair. These cells recognize danger signals through receptors capable of inducing specialized activation programs. The classically known macrophage activation is induced by IFN-gamma, which triggers a harsh proinflammatory response that is required to kill intracellular pathogens. Macrophages also undergo alternative activation by IL-4 and IL-13, which trigger a different phenotype that is important for the immune response to parasites. Here we review the cellular sources of these cytokines, receptor signaling pathways, and induced markers and gene signatures. We draw attention to discrepancies found between mouse and human models of alternative activation. The evidence for in vivo alternative activation of macrophages is also analyzed, with nematode infection as prototypic disease. Finally, we revisit the concept of macrophage activation in the context of the immune response.

Alternative Activation of Macrophages: An Immunologic Functional Perspective

Endothelial Cells in Physiology and in the Pathophysiology of Vascular Disorders

Galectin-3 is a β-galactoside-specific, carbohydrate-recognizing protein (lectin) that is strongly implicated in cancer development, metastasis, and drug resistance. Galectin-3 promotes migration and ability to withstand drug treatment of B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cells. Due to high amino acid conservation among galectins and the shallow nature of their glycan-binding site, the design of selective potent antagonists targeting galectin-3 is challenging. Herein, we report the design and synthesis of novel taloside-based antagonists of galectin-3 with enhanced affinity and selectivity. The molecules were optimized by in silico docking, selectivity was established against four galectins, and the binding modes were confirmed by elucidation of X-ray crystal structures. Critically, the specific inhibition of galectin-3-induced BCP-ALL cell agglutination was demonstrated. The compounds decreased the viability of ALL cells even when grown in the presence of protective stromal cells. We conclude that these compounds are promising leads for therapeutics, targeting the tumor-supportive activities of galectin-3 in cancer.

Novel Selective Galectin-3 Antagonists Are Cytotoxic to Acute Lymphoblastic Leukemia.

The role of epithelial cell surface glycoconjugates in self-not-self and self-self interaction.

Galectin-8 has gained attention as a potential new pharmacological target for the treatment of various diseases, including cancer, inflammation, and disorders associated with bone mass reduction. To that end, new molecular probes are needed in order to better understand its role and its functions. Herein we aimed to improve the affinity and target selectivity of a recently published galectin-8 ligand, 3-O-[1-carboxyethyl]-β-d-galactopyranoside, by introducing modifications at positions 1 and 3 of the galactose. Affinity data measured by fluorescence polarization show that the most potent compound reached a KD of 12 μM. Furthermore, reasonable selectivity versus other galectins was achieved, making the highlighted compound a promising lead for the development of new selective and potent ligands for galectin-8 as molecular probes to examine the protein's role in cell-based and in vivo studies.

Selective Monovalent Galectin-8 Ligands Based on 3-Lactoylgalactoside.

Publisher Summary The ultimate goal of studies on microbial adhesion is to understand what molecular interactions between the host and microbe occur in vivo and the impact of these interactions on disease processes With this goal in mind, the problem can be approached at four levels At the biochemical level, the host receptors at the relevant colonization site are identified; at the cell biology level, consequences of bacterial binding to host epithelial cells are studied in cell culture; at the physiological level, the consequences of bacterial binding are studied in experimental animals or humans; and at the population level, the consequences of receptor binding for colonization are studied by epidemiological methods This chapter provides an example of studies at each level and discusses the implications for what might occur in vivo 

Strategies for studying bacterial adhesion in Vivo

Letter by Leffler Regarding Article, "Modified Citrus Pectin Prevents Blood-Brain Barrier Disruption in Mouse Subarachnoid Hemorrhage by Inhibiting Galectin-3"

Hakon Leffler

Papers

Novel Selective Galectin-3 Antagonists Are Cytotoxic to Acute Lymphoblastic Leukemia.

The role of epithelial cell surface glycoconjugates in self-not-self and self-self interaction.

Selective Monovalent Galectin-8 Ligands Based on 3-Lactoylgalactoside.

Strategies for studying bacterial adhesion in Vivo

Letter by Leffler Regarding Article, "Modified Citrus Pectin Prevents Blood-Brain Barrier Disruption in Mouse Subarachnoid Hemorrhage by Inhibiting Galectin-3"