The whole-cell immobilization of D-hydantoinase-engineered Escherichia coli for D-CpHPG biosynthesis

Background: D-Hydroxyphenylglycine is considered to be an important chiral molecular building-block of antibiotic reagents such as pesticides, and β-lactam antibiotics. The process of its production is catalyzed by D-hydantoinase and D-carbamoylase in a two-step enzyme reaction. How to enhance the catalytic potential of the two enzymes is valuable for industrial application. In this investigation, an Escherichia coli strain genetically engineered with D-hydantoinase was immobilized by calcium alginate with certain adjuncts to evaluate the optimal condition for the biosynthesis of D-carbamoyl-p-hydroxyphenylglycine (D-CpHPG), the compound further be converted to D-hydroxyphenylglycine (D-HPG) by carbamoylase. Result: The optimal medium to produce D-CpHPG by whole-cell immobilization was a modified Luria-Bertani (LB) added with 3.0% (W/V) alginate, 1.5% (W/V) diatomite, 0.05% (W/V) CaCl2 and 1.00 mM MnCl2. The optimized diameter of immobilized beads for the whole-cell biosynthesis here was 2.60 mm. The maximized production rates of D-CpHPG were up to 76%, and the immobilized beads could be reused for 12 batches. Conclusions: This investigation not only provides an effective procedure for biological production of D-CpHPG, but gives an insight into the whole-cell immobilization technology. © 2016 Pontificia Universidad Católica de Valparaíso. Production and hosting by Elsevier B.V. All rights reserved.

The quality of care of diabetic patients in rural Malawi: A case of Mangochi district

Background Diabetes mellitus is a global public health problem. In Malawi, the prevalence of diabetes is 5.6% but the quality of care has not been well studied. Objective The aim of this study was to assess the quality of care offered to diabetic patients in Mangochi district. Methods This was a cross sectional descriptive study. Quantitative data were collected using a questionnaire from a sample of 75 diabetic patients (children and adults) who attended the Diabetes Clinic at Mangochi District Hospital between 20012 and 2013. Qualitative data were also collected using semi-structured interviews with eight Key Informants from among the District Health Management Team. Frequencies and cross-tabulation were obtained from the quantitative data. Patients’ master cards were checked to validate results. Clinical knowledge about diabetes, care practices and resources were the themes analysed from the qualitative data. Results Among the 75 participants interviewed, 46 were females and 29 males. The overall mean age was 48.3 years (45.6 for females and 53.3 for males). More than half of patients had little or no information about diabetes (40.0 % (n=30) and 22.7 (n=17) respectively. The majority of patients were taking their medicines regularly 98.7% (n=74). Only 17.3% (n=13) reported having their feet inspected regularly. Fifty-six percent of patients were satisfied about services provision. Some nurses and clinicians were trained on diabetes care but most of them left. Guidelines on diabetes management were not accessible. There were shortages in medicines (e.g. soluble insulin) and reagents. Information Education and Communication messages were offered through discussions, experiences sharing and posters. Conclusion Quality of diabetes care provided to diabetic patients attended to Mangochi hospital was sub-optimal due to lack of knowledge among patients and clinicians and resources. More efforts are needed towards retention of trained staff, provision of pharmaceutical and laboratory resources and health education.

Low impact to fixed cell processing aiming transmission electron microscopy

In cell culture, cell structures suffer strong impact due to centrifugation during processing for electron microscope observation. In order to minimise this effect, a new protocol was successfully developed. Using conventional reagents and equipments, it took over one week, but cell compression was reduced to none or the lowest deformation possible.