Numerical study of a large diameter shaft in old alluvium

Master'sMASTER OF ENGINEERIN

Key stages in mammary gland development - Involution: apoptosis and tissue remodelling that convert the mammary gland from milk factory to a quiescent organ

Involution of the mammary gland is an essential process that removes the milk-producing epithelial cells when they become redundant at weaning. It is a two-step process that involves the death of the secretory epithelium and its replacement by adipo-cytes. During the first phase, remodelling is inhibited and apoptotic cells can be seen in the lumena of the alveoli. In the second phase, apoptosis is accompanied by remodelling of the surrounding stroma and re-differentiation of the adipocytes. Considerable effort has been directed towards understanding the molecular mechanisms of the involution process and this has resulted in the identification of the principal signalling pathways involved

Construction of uricase-overproducing strains of Hansenula polymorpha and its application as biological recognition element in microbial urate biosensor

<p>Abstract</p> <p>Background</p> <p>The detection and quantification of uric acid in human physiological fluids is of great importance in the diagnosis and therapy of patients suffering from a range of disorders associated with altered purine metabolism, most notably gout and hyperuricaemia. The fabrication of cheap and reliable urate-selective amperometric biosensors is a challenging task.</p> <p>Results</p> <p>A urate-selective microbial biosensor was developed using cells of the recombinant thermotolerant methylotrophic yeast <it>Hansenula polymorpha </it>as biorecognition element. The construction of uricase (UOX) producing yeast by over-expression of the uricase gene of <it>H. polymorpha </it>is described. Following a preliminary screening of the transformants with increased UOX activity in permeabilized yeast cells the optimal cultivation conditions for maximal UOX yield namely a 40-fold increase in UOX activity were determined.</p> <p>The UOX producing cells were coupled to horseradish peroxidase and immobilized on graphite electrodes by physical entrapment behind a dialysis membrane. A high urate selectivity with a detection limit of about 8 μM was found.</p> <p>Conclusion</p> <p>A strain of <it>H. polymorpha </it>overproducing UOX was constructed. A cheap urate selective microbial biosensor was developed.</p