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Cross-linked magnetic chitosan beads were prepared in presence of epichlorohydrin under alkaline conditions, and subsequently incubated with glutaraldehyde in order to obtain an activated support for covalent attachment of nucleoside 2'-deoxyribosyltransferase from Lactobacillus reuteri (LrNDT). Changing the amount of magnetite (Fe3O4) and epichlorohydrin (EPI) led to different macroscopic beads to be used as supports for enzyme immobilization, whose morphology and properties were characterized by scanning electron microscopy, spin electron resonance (ESR), and vibrating sample magnetometry (VSM). Once activated with glutaraldehyde, the best support was chosen after evaluation of immobilization yield and product yield in the synthesis of thymidine from 2'-deoxyuridine and thymine. In addition, optimal conditions for highest activity of immobilized LrNDT on magnetic chitosan were determined by response surface methodology (RSM). Immobilized biocatalyst retained 50 % of its maximal activity after 56.3 h at 60 °C, whereas 100 % activity was observed after storage at 40 °C for 144 h. This novel immobilized biocatalyst has been successfully employed in the enzymatic synthesis of 2'-deoxyribonucleoside analogues as well as arabinosyl-nucleosides such as vidarabine (ara-A) and cytarabine (ara-C). Furthermore, this is the first report which describes the enzymatic synthesis of these arabinosyl-nucleosides catalyzed by an immobilized nucleoside 2'-deoxyribosyltransferase. Finally, the attached enzyme to magnetic chitosan beads could be easily recovered and recycled for 30 consecutive batch reactions with negligible loss of catalytic activity in the synthesis of 2,6-diaminopurine-2'-deoxyriboside and 5-trifluorothymidine.; 2.505 JCR (2013) Q2, 61/165 Biotechnology & applied microbiology

OBJECTIVES: to evaluate the outcome and cost of transfer to a nursing-led inpatient unit for ‘intermediate care’. The unit was designed to replace a period of care in acute hospital wards and promote recovery before discharge to the community. DESIGN: randomized controlled trial comparing outcomes of care on a nursing-led inpatient unit with the system of consultant-managed care on a range of acute hospital wards. SETTING: hospital wards in an acute inner-London National Health Service trust. SUBJECTS: 175 patients assessed to be medically stable but requiring further inpatient care, referred to the unit from acute wards. INTERVENTION: 89 patients were randomly allocated to care on the unit (nursing-led care with no routine medical intervention) and 86 to usual hospital care. MAIN OUTCOME MEASURES: length of hospital stay, discharge destination, functional dependence (Barthel index) and direct healthcare costs. RESULTS: care in the unit had no significant impact on discharge destination or dependence. Length of inpatient stay was significantly increased for the treatment group (P=0.036; 95% confidence interval 1.1–20.7 days). The daily cost of care was lower on the unit, but the mean total cost was £1044 higher—although the difference from the control was not significant (P=0.150; 95% confidence interval -£382 to £2471). CONCLUSIONS: the nursing-led inpatient unit led to longer hospital stays. Since length of stay is the main driver of costs, this model of care—at least as implemented here—may be more costly. However, since the unit may substitute for both secondary and primary care, longer-term follow-up is needed to determine whether patients are better prepared for discharge under this model of care, resulting in reduced primary-care costs.