Glycan Subject

Parasitism by T. spiralis has been a subject of scientific interest for over 150 years. Recently, considerable attention has been paid to the parasite by immunologists interested in immunity to nematodes in general, and mucosal immunity in particular. It has been shown that glycan-specific antibodies are highly effective mediators of host defence against intestinal 7. spiralis infection. Protective monoclonal antibodies have been used to elucidate mechanisms of worm expulsion, as well as to identify molecules that the parasite uses to create its niche. In the future, detailed characterization of these molecules and their functions should afford additional insights into parasitism by Trichinella spiralis, and possibly also by other types of pathogen. 

Acid-labile linkages of carbohydrates are commonly those of furano-sidic sugar residues or of deoxy monosaccharides.50,63 Consequently, neuraminic acid and fucose residues, which occur as terminal monosaccharides of protein- and lipid-linked glycans, are removed by hydrolysis with a dilute acid. The linkages formed by these two sugar residues can conveniently be differentiated by subjecting a portion of... 

Then, little by little, it began to be suggested that the glycans could well play an important biological role, and we may summarize the hypotheses, based on experimental results that have been obtained on this subject up to the present time (for reviews, see Refs. 8 to 20), as follows, a. The hypothesis of the induction of protein conformation is... 

Fig. 15. Differentiation of mouse P19C6 cells to neural cells, and N-glycan changes as monitored by the glycoblotting method. Undifferentiated cells were stimulated by retinoic acid, and the cells were subjected to the glycoblotting protocol optimized for cellular glycomics. It was demonstrated that the expression level of various bisecting-type N-glycans increased drastically during cell differentiation to neural cells.91 Three glycoforms circled by red lines are known to exist in the mouse brain system.92 93 (This figure was made by the author.)...

The assembly of complex glycans via either a linear or a block approach is often subject to tedious purification (chromatography) steps that lower the overall chemical yield. It would be desirable to use an approach that strives to lower the number of purifications, particularly as the synthesis advances. Toward this end, many groups have developed and refined one-pot... 

In this context, the production of a large quantity of fine sialo-glycans and its conjugates with lipid or protein (peptide) has been a critical subject. 

Bones are constantly subjected to forces that cause microscopic cracks. These microcracks (1) attach blood monocytes circulating within the periosteum and bone marrow and (2) induce adjacent osteoblasts to produce cytokines (Sect. 3.3.2) that cause these monocytes to proliferate, fuse, and differentiate into large multinucleated cells called osteoclasts. Osteoclasts cause bone resorption by acid demineralization and digestion of its proteins by enzymes that are optimally active in an acidic environment. These proteases and other hydrolytic enzymes are stored in a specialized, membrane-sealed compartment (lysosomes) into which they are guided by possessing terminal mannose 6-phosphate residues on N-linked glycans. 

Counts of the number of S. mutans or L. casei are a poor measure of caries susceptibility because as noted above, they cannot account for ammonia production or differences in glycan production by other bacteria in the biofilms. Acid production after a 10% sucrose or glucose rinse after a 6 h or longer fast is a better measure of caries susceptibility, because it represents the balanced outcome of the factors that promote or prevent caries. Because this method requires time and skill, it is difficult to apply to many subjects. A simpler method of measuring caries susceptibility is past caries experience and age. The more teeth affected by caries in a child or adolescent, the greater is the likelihood that a new cavity will develop and, therefore, the greater is the need for preventive measures. Unfortunately, this measure is completely uninformative about what factors are present to promote or prevent caries. 

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