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d-pantolactone is an intermediate in the synthesis of d-pantothenic acid, which is known as vitamin B5. The commercial synthesis of d-pantolactone is carried out through the selective resolution of dl-pantolactone catalyzed by lactone hydrolase. In contrast to a kinetic resolution approach, the deracemization of dl-pantolactone is a simpler, greener, and more sustainable way to obtain d-pantolactone with high optical purity. Herein, an efficient three-enzyme cascade was developed for the deracemization of dl-pantolactone, using l-pantolactone dehydrogenase from Amycolatopsis methanolica (AmeLPLDH), conjugated polyketone reductase from Zygosaccharomyces parabailii (ZpaCPR), and glucose dehydrogenase from Bacillus subtilis (BsGDH). The AmeLPLDH was used to catalyze the dehydrogenated l-pantolactone into ketopantolactone; the ZpaCPR was used to further catalyze the ketopantolactone into d-pantolactone; and glucose dehydrogenase together with glucose fulfilled the function of coenzyme regeneration. All three enzymes were co-expressed in E. coli strain BL21(DE3), which served as the whole-cell biocatalyst. Under optimized conditions, 36 h deracemization of 1.25 M dl-pantolactone d-pantolactone led to an e.e.p value of 98.6%, corresponding to productivity of 107.7 g/(l·d).

To investigate the effect on improving immune function by hemofiltration combined with hemoabsorption in septic patients with low human leukocyte antigen DR (HLA-DR) expression.A prospective randomized controlled trial was conducted. Sixty sepsis patients aged over 18 years, with HLA-DR expression lower than 30% were enrolled, and they were randomly divided into experimental group and control group, n = 30 in each group. The patients were treated with standard operating procedure for sepsis, and hemofiltration combined with hemoabsorption were added in addition in the experimental group within 1-3 days. The continuous venovenous hemofiltration (CVVH) mode was performed, with former dilution volume 4 L/h, and the hemofilter HF2000 was carried out with blood absorber HA-330H. The expression of HLA-DR in peripheral blood mononuclear cells was determined before the treatment and 3, 5, 7 days after treatment. Acute physiology and chronic health evaluation II (APACHE II) score, duration of mechanical ventilation, length of intensive care unit (ICU) stay, and 28-day survival rate were evaluated in both groups.The HLA-DR expression before treatment in experimental group and control group was both lower than 30%, and there was no statistical difference [(25.9 ± 7.3)% vs. (26.4 ± 6.7)%, P0.05]. The HLA-DR expression at 3, 5, 7 days after treatment in experimental group was gradually increased, and it was significantly higher than that of the control group [3 days: (38.9 ± 8.6)% vs. (29.3 ± 7.1)%, 5 days: (42.7 ± 9.2)% vs. (31.4 ± 6.5)%, 7 days: (40.9 ± 8.5)% vs. (29.4 ± 6.7)%, all P0.05]. There was no significant difference in APACHE II score before treatment between experimental group and control group (22.4 ± 5.3 vs. 21.7 ± 6.2, P0.05). APACHE II score at 3, 5, and 7 days after treatment was gradually decreased in experimental group, and it was obviously lower than that of the control group (3 days: 18.6 ± 3.6 vs. 20.5 ± 4.3, 5 days: 15.8 ± 3.9 vs. 21.1 ± 4.4, 7 days: 14.9 ± 4.2 vs. 19.8 ± 3.7, all P0.05). Compared with the control group, the duration of mechanical ventilation (days: 13.3 ± 3.4 vs. 19.8 ± 3.7, t = 6.432, P = 0.003) and length of ICU stay (days: 20.7 ± 3.9 vs. 26.8 ± 4.7, t = 5.452, P = 0.006) in experimental group were significantly shortened, and the 28-day survival rate was significantly elevated (83.3% vs. 73.3%, χ2 = 3.121, P = 0.016).Hemofiltration combined with hemoabsorption can improve the expression of HLA-DR in sepsis patients with low expression of HLA-DR, and it can improve immune function and prognosis of sepsis patients in certain degree.

A multi-band hybrid PIFA/loop antenna is proposed for the application of mobile communications terminals. The antenna is an internal antenna and very compact in comparison with conventional mobile antennas. It has been demonstrated that the proposed antenna can cover all the commonly required WLAN frequency bands, including 2.4 GHz (2.4–2.484 GHz), 5.2 GHz (5.15–5.35 GHz), and 5.8 GHz (5.725–5.825 GHz).

The article mainly discusses the design objective of an object oriented database management system called OMNIX. It explains the function and structure, as well as the implementation of the whole system.