Structural aspects of human gastric gel mucin

The structure of human gastric gel mucin, a fucomucin of very high molecular weight, was studied by analyzing the effects of alkali treatment. The gel mucin was seen to undergo a β-elimination reaction as judged by the loss of both threonine and serine residues, the production of α-amino butyric acid and alanine residues in a reducing system, the formation of α-ketobutyric acid and pyruvic acid residues in a non-reducing system and the substantial decrease in molecular weight of the mucin after alkali treatment. It is concluded that gel mucin has polysaccharide side-chains of exceptionally large size, joined O-glycosidically to the protein core. As the existence of disulphide crosslinks in the protein is not supported, it is proposed that the maintenance of the 'rigidity' of the gel structure is due to carbohydrate interactions between molecules

The definition of acute kidney injury and its use in practice.

Acute kidney injury (AKI) is a common syndrome that is independently associated with increased mortality. A standardized definition is important to facilitate clinical care and research. The definition of AKI has evolved rapidly since 2004, with the introduction of the Risk, Injury, Failure, Loss, and End-stage renal disease (RIFLE), AKI Network (AKIN), and Kidney Disease Improving Global Outcomes (KDIGO) classifications. RIFLE was modified for pediatric use (pRIFLE). They were developed using both evidence and consensus. Small rises in serum creatinine are independently associated with increased mortality, and hence are incorporated into the current definition of AKI. The recent definition from the international KDIGO guideline merged RIFLE and AKIN. Systematic review has found that these definitions do not differ significantly in their performance. Health-care staff caring for children or adults should use standard criteria for AKI, such as the pRIFLE or KDIGO definitions, respectively. These efforts to standardize AKI definition are a substantial advance, although areas of uncertainty remain. The new definitions have enabled the use of electronic alerts to warn clinicians of possible AKI. Novel biomarkers may further refine the definition of AKI, but their use will need to produce tangible improvements in outcomes and cost effectiveness. Further developments in AKI definitions should be informed by research into their practical application across health-care providers. This review will discuss the definition of AKI and its use in practice for clinicians and laboratory scientists