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Different analytical methods have been developed to effectively and accurately determine monosaccharide composition of glycoproteins and glycolipids in biological and biomedical samples. These methods included high-performance anion-exchange chromatography with pulse amperometric detection (HPAEC-PAD), high-performance liquid chromatography with fluorescence detection (HPLC-FL), and capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). This chapter reviews the development of these methods, and evaluates their potential application in the diagnosis or prognosis of diseases. [ABSTRACT FROM AUTHOR]

The evolution of the horse was certainly a most tortuous process. None of your seven day nonsense! Seven days' labour wouldn't evolve one primitive earthworm. There are interesting parallels between the structuring of multicellular organisms and societies. We see the same elements of aggregation, communication, commitment and differentiation, and although some regret the decline of the protean ideal, specialization was a minor penalty to pay for the development of modern society. After all, more people have flown in aeroplanes than ever held a pilot's licence, and more have enjoyed the benefits of surgery than ever wielded a scalpel. And how many of us would be meat eaters if we had to do our own butchering? There are even similarities in the way societies and multicellular organisms subordinate the individual to the point of dispensability. A nation survives the death of any citizen, however prominent, and a mature organism hardly seems to notice replacement of its individual cells. Moreover, it now appears that the collective structure has a vested interest in the mortality of its members; the multicellular organism follows a policy of programmed death, and a steady turnover increases the chance of a favourable mutation. This too might have its social counterpart; what happens to individual members after they have procreated is of minor importance, and old worn-out citizens are replaced by fresh young individuals. [ABSTRACT FROM AUTHOR]

A million million spermatozoa, All of them alive: Out of their cataclysm but one poor Noah Dare hope to survive. And among that billion minus one Might there have chanced to be Shakespeare, another Newton, a new Donne, But the One was Me. Although biopolymers are more sophisticated than their simpler cousins, such as polythene and rubber, this alone does not give them an obvious reason for existing. Nucleic-acid codes for proteins, some of which contribute to the formation of further nucleic acid, but if these products were free to float away through the surrounding water, no advantage would be gained by the original molecule. The essential extra factor was discovered over 300 years ago. In 1663, using one of the earliest microscopes, Robert Hooke observed that cork has a structure reminiscent of a honeycomb, with pores separated by diaphragms so as to produce a collection of little boxes, which he called cells. Their universality was not appreciated until 1824, when Henri Dutrochet concluded that entire animals and plants are aggregates of cells, arranged according to some definite plan. He also suggested that growth is caused by an increase in either cell size or cell number, or both. The idea of the cell was further elevated in 1838, when Matthias Schleiden proposed that it is the basic structural unit in all organisms. [ABSTRACT FROM AUTHOR]

There is no excellent beauty that hath not some strangeness in the proportion. Most substances can exist in three different states: solid, liquid and gas. The temperature, pressure and density collectively determine which form is adopted, and changes in the imposed conditions can produce the melting and boiling phase transitions. The solid state is usually crystalline, but some solids have the meta-stable glass structure. Differences between the three fundamental states are often depicted by simple diagrams in which atoms are represented by circles. For a gas, the circles are drawn randomly, with the distance between neighbouring circles somewhat larger than the circle diameter. The condensed states, crystal and liquid, are illustrated by arrangements in which the distances between the centres of neighbouring circles are comparable to the diameters, the difference between these forms lying mainly in the regular arrangement of the former and the relative randomness of the latter. We can go a long way with such models because real atoms are indeed roughly spherical. This is particularly true for noble gases such as argon and neon, because of their closed electron shells, but it is a reasonable approximation for all atoms. The question arises as to what happens if the atoms are replaced by molecules elongated in one direction. The answer is to be found in that peculiar intermediate state of matter: the liquid crystal. A description of arrangements in terms of positions of centres of gravity is inadequate for elongated molecules. [ABSTRACT FROM AUTHOR]

This chapter focusesGlycolipids on the occurrence and the physicochemical properties of glycolipids in Nature. Owing to space limitations, the presented overview must be incomplete, and, thus, mainly publications of the past 15 years are included. However, all review articles cited herein inform the interested reader about earlier work. Although lipopolysaccharides (LPS), lipoarabinomannan (LAM), lipomannan, lipoglycans, and lipoteichoic acids are not understood as glycolipids per definition, their occurrence and properties are also described in this chapter. GPI-anchored lipids is a main topic of Chap. 7.4 . [ABSTRACT FROM AUTHOR]

Glycolipids are an important group of diverse molecules present in the plasma membrane and to a more limited extent in the intracellular membranes of the Golgi and lysosomal systems of eukaryotic cells. They are prominent as antigenic determinants and as the ligands for specific lectin binding, and there are many examples in which they have been used as cell specific markers. The cellular glycolipid pattern frequently shows changes with the state of differentiation and may be altered following viral transformation. In animal cells the most common and most varied glycolipids are glycosphingolipids, and the methods of isolation and analysis given are mainly for this class of molecule. Methods are given for the extraction of total glycolipid from small volumes of tissue and for the isolation of the glycolipids from such extracts. Methods of fractionating and quantitating the acidic and neutral glycolipids are described, which do not require the use of specialized equipment such as high-performance liquid chromatography (HPLC), gas chromatography (GC), or mass spectroscopy and which can be performed easily in the general laboratory. [ABSTRACT FROM AUTHOR]

A definition of the term "CD15" is presented. It refers to a carbohydrate antigen called the X hapten, found in several glycolipids and glycoproteins. CD15 is present on normal myeloid cells and a wide variety of epithelial cells, as well as their corresponding tumors.