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Aims and objectives: To assess the effects of three different bowel preparation methods on the incidence of infectious complications in patients who underwent transrectal ultrasonography‐guided prostate biopsy. Background: The standard bowel preparation protocol for prostate biopsy has not been established. Design: A retrospective study in a single centre. Methods: From January 2013–December 2015, the clinical records of 1,130 patients who underwent prostate biopsy were, respectively, reviewed. All the patients received metronidazole prophylaxis before biopsy. The patients were divided into three groups according to the bowel preparation methods: patients in Group A (n = 402) received only soapy enema; patients in Group B (n = 413) received polyethylene glycol; while patients in Group C (n = 315) received polyethylene glycol plus povidone–iodine enema. Infectious complications were classified as fever (>37.5°C), urinary tract infection and sepsis. The postoperative adverse events were also observed. Results: The overall postbiopsy infectious complications were observed in 48 (4.25%) patients of all the cases, including 23 (5.72%) cases in Group A, 20 (4.84%) cases in Group B and five patients (1.59%) in Group C. There was significant difference among the groups (p = .018). In detail, these infectious complications included 22 (1.95%) cases of fever and 26 (2.30%) cases of urinary tract infection. No sepsis was observed among the total patients. The incidence of adverse events was 14.43% (58/402) occurred in Group A, 25.91% (107/413) in Group B and 26.67% (84/315) in Group C. The difference was statistically significant. Conclusions: Our study confirmed that combined preparation regimens of polyethylene glycol with povidone–iodine enema could significantly reduce the postbiopsy infection rate. Conventional soapy enema is associated with less adverse events. Relevance to clinical practice: Findings of this study provide useful evidence‐based information for healthcare professionals. The application of combined preparation regimens of polyethylene glycol with povidone–iodine enema resulted in better improvement in the prevention of postbiopsy infection. [ABSTRACT FROM AUTHOR]

A recirculating packed bed reactor (RPBR) was used for efficient production ofR-mandelic acid (R-MA) by kinetic resolution of racemicR,S-mandelonitrile (R,S-MN) using the recombinantE. colicells crosslinked with diatomite (DA)/glutaraldehyde (GA)/polyethyleneimine (PEI). The performance and productivity of RPBR were evaluated by several parameters, including cell load, substrate feeding rate, height diameter (H/D) ratio, reactor structures, and operation stability. The kinetic resolution process showed higher initial reaction rate (1.52 mM/min) and yield (100%) by recycling 100 mL of substrate solution (70 mM) through RPBR packed with 6.0 g immobilized cells at a substrate-feeding rate of 19 mL/min while the H/D ratio was 2.8. The immobilized cells were successfully applied into kinetic resolution ofR,S-MN in the RPBR for 50 batches with an average productivity of 4.12 g/L/h forR-MA with >99% of enantiomeric excess. [ABSTRACT FROM AUTHOR]

( R)-(−)-Mandelic acid ( R-MA) is widely used both as a versatile intermediate for pharmaceuticals and a resolving agent in chiral resolution processes. In the current study, to improve the stability of operation, recombinant Escherichia coli cells expressing nitrilase from Alcaligenes faecalis were immobilized for the enantioselective hydrolysis of ( R, S)-mandelonitrile to R-MA. Different immobilization methods including entrapment matrices, entrapment matrices cross-linked by cross-linking and polymerization agents, and direct cross-linking cells using glutaraldehyde (GA) or bionic silicon were investigated. To facilitate industrial solid-liquid separation, the direct cross-linking recombinant E. coli cells using diatomite/GA/polyethyleneimine with 135.95% relative activity compared with free cells was chosen using water as the reaction medium. The operational stability of the immobilized cells was obviously superior to that of free cells, without significant activity loss after 28 cycles of batch reaction and the successive production of R-MA could reach 1.88 M. Moreover, the immobilized cells showed good storage stability with about 52% relative activity after storing for 30 days at 4 °C. Therefore, the immobilized biocatalyst is very promising for upscale production of optically pure R-MA with high performance and low cost. [ABSTRACT FROM AUTHOR]

A nitrilase gene from Acidovorax facilis ZJB09122 was cloned and expressed in Escherichia coli BL21 (DE3). To improve the activity of this nitrilase, a key amino acid Phe168 was selected and mutated by site-directed mutagenesis, based on the homology modeling and previously described “hot spot” mutation. After mutation and screening, a mutant (Mut-F168V) with higher activity and stability was obtained. The nitrilase activity of Mut-F168V to hydrolyze 1-cyanocyclohexylacetonitrile was 39.52-fold compared with wild type A. facilis nitrilase (Wt-Acf-Nit). The values of K m and V max of Mut-F168V were markedly decreased to 1.89-fold and increased to 50.34-fold as compared to Wt-Acf-Nit, respectively. The biotransformation study showed that 1.0 M of 1-cyanocyclohexylacetonitrile could be regioselectively hydrolyzed to 1-(cyanocyclohexyl) acetic acid with 90% yield. The yield of 1-(cyanocyclohexyl) acetic acid by Mut-F168V was 66.19-fold compared to Wt-Acf-Nit after 1 h at the concentration of 1.0 M 1-cyanocyclohexylacetonitrile as substrate. The 1-(cyanocyclohexyl) acetic acid was subsequently isolated and characterized. The mutant (Mut-F168V) appears promising for potential applications for the industrial production of 1-(cyanocyclohexyl) acetic acid. [ABSTRACT FROM AUTHOR]

Iminodiacetic acid (IDA) is widely used as an intermediate in the manufacturing of chelating agents, glyphosate herbicides and surfactants. To improve activity and tolerance to the substrate for IDA production, Acidovorax facilis nitrilase was selected for further modification by the gene site saturation mutagenesis method. After screened by a two-step screening method, the best mutant (Mut-F168V/T201N/S192F/M191T/F192S) was selected. Compared to the wild-type nitrilase, Mut-F168V/T201N/S192F/M191T/F192S showed 136% improvement in specific activity. Co 2+ stimulated nitrilase activity, whereas Cu 2+ , Zn 2+ and Tween 80 showed a strong inhibitory effect. The V max and k cat of Mut-F168V/T201N/S192F/M191T/F192S were enhanced 1.23 and 1.23-fold, while the K m was decreased 1.53-fold. The yield of Mut-F168V/T201N/S192F/M191T/F192S with 453.2 mM of IDA reached 71.9% in 5 h when 630 mM iminodiacetonitrile was used as substrate. This study indicated that mutant nitrilase obtained in this study is promising in applications for the upscale production of IDAN. [ABSTRACT FROM AUTHOR]

Iminodiacetic acid (IDA) is widely used as an intermediate in the manufacture of chelating agents, glyphosate herbicides and surfactants. In the current work, the fragment with the length of 1,110 bp encoding the Acidovorax facilis nitrilase was obtained. The recombinant nitrilase expressed in Escherichia coli BL21 (DE3) was successfully used in the production of IDA from iminodiacetonitrile. To improve the stability of operation, the recombinant cells were entrapped in polyvinyl alcohol (PVA) and sodium alginate (SA) copolymer. The maximum relative nitrilase activity with 98.1% was further observed at 1.0% SA, 8.0% PVA, 1.0% CaCl2, and 5.0% wet cells, under conditions of 1.0% iminodiacetonitrile in distilled water and a temperature of 40°C, respectively. The entrapped cells facilitated easy separation and good recycling compared with free cells. Moreover, the immobilized cells showed good operation and storage stability. This report is the first to describe IDA preparation using immobilized recombinant E. coli harboring nitrilase. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Few data are available on the role of neutrophil elastase (NE) and nuclear factor-κB (NF-κB) in the course of seawater drowning-induced acute lung injury (SWD-ALI), and there is no evidence on the value of giving urinary trypsin inhibitor (UTI) in the case of SWD-ALI. Objective: To investigate the role of NF-κB and NE in the pathogenesis of SWD-ALI and whether UTI treatment can attenuate SWD-ALI in rabbits. Methods: Rabbits were randomly assigned to control, seawater drowning, and UTI treatment groups. The rabbits in the control group only suffered from intubation, whereas the rabbits in the seawater drowning group and the UTI treatment group received arterial injection of normal saline without/with 50,000 U/kg body weight of UTI after instillation of seawater into an endotracheal catheter. The activities or contents of NF-κB, MPO, NE, TNF-α, and IL-10 in lung tissue were measured by nonradioactive EMSA, biochemical methods, and ELISA, respectively. Results: After the seawater challenge, all of the rabbits demonstrated immediate drops in arterial PaO2/FiO2 and pronounced pulmonary edema and inflammatory cell infiltration with evidence of an increase in the ratio of wet weight to dry weight, lung permeability index, lung injury scores, and the activities or contents of NF-κB, NE, MPO, TNF-α, and IL-10. UTI treatment markedly attenuated lung histopathological changes with evidence of a decrease in all of the parameters, except for upregulation of IL-10. Arterial PaO2/FiO2 was significantly improved after 6 h of UTI treatment. Conclusion: These results suggest that NF-κB and NE play an important role in SWD-ALI. UTI protects against SWD-ALI, at least partly, through inhibition of the enhanced local activity of NF-κB, contents of TNF-α and NE, and infiltration of neutrophils and promotion of the level of IL-10. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We sequenced a chronic obstructive pulmonary diseaseRattus norvegicusC57CE strain mitochondrial genome for the first time (GenBank Accession No. KM114607). Its mitogenome was 16,307 bp and coding 13 protein–coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes. This genome will provide definite information for genetic perspective into this disease. [ABSTRACT FROM PUBLISHER]

The strong aromatic Chinese liquors are batch-brewed in mud cellars, but the changes in the brewing microflora and their effects on the production of flavors are mostly unclear. In the liquor brewing industry, it is a mystery that older cellars produce better tasting liquors. In this study, by pyrosequencing the 16S rRNA gene, we found that the microflora in a 10-year-old cellar and a 1-year-old cellar significantly reduced the differences of microbial communities between the top, middle and bottom mud layers, but became surprisingly more diverse in the old cellar than that in the new cellar. Gas chromatography-mass spectrometry assays indicated that the liquors produced in the old cellar contained higher concentrations of certain ester ingredients that are important for the liquor flavor. We further demonstrated that different bacterial isolates from cellar mud were all able to produce diverse organic compounds. These results indicate that long-term spontaneous batch-fermentation accumulates diverse adaptive microbes, which comprehensively produce more flavorful Chinese liquors. [ABSTRACT FROM AUTHOR]