Stigma evaluation for diabetes and other chronic non-communicable disease patients: Development, validation and clinical use of stigma scale - The Kanden Institute Stigma Scale.

AIMS/INTRODUCTION: The aim of this study was to develop a scale to evaluate disease stigma in patients with lifestyle-related chronic non-communicable diseases (LCNCDs), which we named the Kanden Institute Stigma Scale (KISS), and to consider its possible clinical application for patients with diabetes. MATERIALS AND METHODS: An initial 90 questions were drafted and categorized into six subscales according to the manifestations of stigma. The final version of the KISS was developed as a 24-item questionnaire comprising four items for each subscale. RESULTS: A total of 539 outpatients including 452 patients with diabetes and 87 patients without diabetes were recruited. Construct validity was confirmed by assessing the correlation with previously established measures. Confirmatory factor analysis showed the KISS to have good model fitness (adjusted goodness-of-fit index = 0.856). Test-retest reproducibility analysis showed that the intraclass coefficient of the first and a second KISS was 0.843 (P < 0.001), indicating excellent reproducibility. The KISS showed higher scores for patients with diabetes than for patients without diabetes (12.23 ± 0.49 vs 5.76 ± 0.73, P < 0.05). The KISS score was significantly higher in type 1 and type 2 diabetes patients taking insulin therapy than in type 2 diabetes patients not taking insulin (P < 0.05). CONCLUSION: The KISS is a validated and reliable questionnaire for assessment of stigma among patients with diabetes as well as other lifestyle-related chronic non-communicable diseases, and might contribute to identifying and rectifying diabetes stigma, as well promoting awareness among health care professionals of this very consequential health problem.

Pyruvate kinase deletion as an effective phenotype to enhance lysine production in Corynebacterium glutamicum ATCC13032: Redirecting the carbon flow to a precursor metabolite.

Various attempts have been made to enhance lysine production in Corynebacterium glutamicum. Pyruvate kinase (PYK) defect is one of the strategies used to enhance the supply of oxaloacetic acid (OAA), a precursor metabolite for lysine biosynthesis. However, inconsistent effects of this mutation have been reported: positive effects of PYK defect in mutants having phosphoenolpyruvate carboxylase (PEPC) desensitized to feedback inhibition by aspartic acid, while negative effects in simple PYK gene (pyk) knockout mutants. To address these discrepancies, the effects of pyk deletion on lysine yield were investigated with or without the D299N mutation in ppc rendering PEPC desensitization. C. glutamicum ATCC13032 mutant strain P with a feedback inhibition-desensitized aspartokinase was used as the parent strain, producing 9.36 g/L lysine from 100 g/L glucose in a jar fermentor culture. Under these conditions, while the simple mutant D2 with pyk deletion or R2 with the PEPC-desensitization mutation showed marginally increased lysine yield (∼1.1-fold, not significant), the mutant DR2 strain having both mutations showed synergistically increased lysine productivity (1.38-fold, 12.9 g/L). Therefore, the pyk deletion is effective under a PEPC-desensitized background, which ensures enhanced supply of OAA, thus clarifying the discrepancies. A citrate synthase defective mutation (S252C in gltA) further increased the lysine yield in strain DR2 (1.68-fold, 15.7 g/L). Thus, these three mutations coordinately enhanced the lysine yield. Both the malate:quinone oxidoreductase activity and respiration rate were significantly reduced in strains D2 and DR2. Overall, these results provide valuable knowledge for engineering the anaplerotic reaction to increase lysine yield in C. glutamicum.