Association of ticagrelor with risk of infection：a two-sample Mendelian randomization study based on the GWAS database / 中国药房

OBJECTIVE To investigate the causal association between ticagrelor and risk of infection METHODS Two-sample Mendelian randomization was adopted. Genetic instrumental variables were selected based on the results of the largest genome-wide association analysis to in vivo exposure of ticagrelor and its major active metabolite AR-C124910XX. The causal associations of ticagrelor and its major active metabolite AR-C124910XX with drug indications （coronary artery disease， unstable angina pectoris， myocardial infarction， stroke and ischemic stroke）were analyzed by inverse variance weighted Mendelian randomization model as a positive control for genetic instrumental variables. The causal relationship between ticagrelor and bacterial infection， acute lower respiratory infection， bacterial pneumoniae， pneumoniae，acute upper respiratory infection and sepsis were furtheranalyzed by using this method， and the robustness of the results was assessed by using heterogeneity tests and horizontal 202002030415） pleiotropy tests. RESULTS The increase of area under the curve at steady state （AUCss） of the genetic surrogated ticagrelor significantly reduced the risk of coronary artery disease， myocardial infarction and unstable angina pectoris （P＜0.001）. AUCss genetic instrument variables of its main active metabolite AR-C124910XX failed to pass positive control. Further analysis showed that the increase of the genetic surrogated ticagrelor exposure suggestively reduced the risk of bacterial infection [OR（95%CI）＝0.80（0.65，0.99），P＝0.040] and sepsis [OR （95%CI）＝0.84（0.73， 0.98）， P＝0.023]. The results of the heterogeneity tests showed that there was no heterogeneity in the causal association of the genetic surrogated ticagrelor AUCss with bacterial infection and sepsis （P＞0.05）. The results of horizontal pleiotropy tests showed that the causal association of genetic surrogated ticagrelor AUCss with bacterial infection and sepsis had no effects on horizontal pleiotropy （P＞0.05）. CONCLUSIONS Ticagrelor has a potential role in reducing the risk of sepsis and bacterial infections.

Optimization of the fermentation conditions for 5-keto-D-gluconic acid production / 生物工程学报

Gluconobacter oxydans converts glucose to gluconic acid and subsequently to 5-keto-D-gluconic acid (5-KGA), a precursor of industrially important L(+)-tartaric acid. To increase the yield of 5-KGA, fermentation conditions of 5-KGA production was optimized. Under the optimum medium and culture conditions in the shake flask, the highest 5-KGA production reached 19.7 g/L, increased by 43.8% after optimization. In a 5-L bioreactor, the pH was controlled at 5.5 and dissolved oxygen (DO) at 15%, 5-KGA production reached 46.0 g/L, raised at least 1.3 times than in the shake flask. Glucose feeding fermentation process was further developed, and the highest 5-KGA production of 75.5 g/L with 70% of yield was obtained, 32.0% higher than the highest reported value. Therefore, this newly developed fermentation process provided a practical and effective alternative for the commercial production of 5-KGA, and further of L(+)-tartaric acid.

Production of L(+)-tartaric acid by immobilized Rhizobium strain BK-20 / 生物工程学报

The cis-epoxysuccinate hydrolase (CESH) from Rhizobium strain BK-20 is the key enzyme for L(+)-tartaric acid production. To establish a highly efficient and stable production process, we first optimized the enzyme production from Rhizobium strain BK-20, and then developed an immobilized cell-culture process for sustained production of L(+)-tartaric acid. The enzyme activity of free cells reached (3 498.0 +/- 142.6) U/g, and increased by 643% after optimization. The enzyme activity of immobilized cells reached (2 817.2 +/- 226.7) U/g, under the optimal condition with sodium alginate as carrier, cell concentration at 10% (W/V) and gel concentration at 1.5% (W/V). The immobilized cells preserved high enzyme activity and normal structure after 10 repeated batches. The conversion rate of the substrate was more than 98%, indicating its excellent production stability.