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Many volatile compounds, such as isoprene, a precursor used in the synthesis of natural rubber, have been produced through fermentation using genetically engineered microorganisms. Despite this biotechnological success, measuring the concentrations of volatile compounds during fermentation is difficult because of their high volatility. In current systems, off-line analytical methods usually lead to product loss, whereas on-line methods raise the production cost due to the requirement of complex devices. Here, we developed a novel on-line gas chromatography (GC)-based system for analyzing the concentration of isoprene with the aim to minimize the cost and requirement for devices as compared to current strategies. In this system, a programmable logic controller is used to combine conventional GC with a syringe pump module (SPM) directly connected to the exhaust pipe of the fermentor, and isoprene-containing samples are continuously pumped from the SPM into the GC using an air cylinder recycle stream. We showed that this novel system enables isoprene analysis during fermentation with convenient equipment and without the requirement of an expensive desorption tube. Furthermore, this system may be extended to the detection of other volatile organic compounds in fermentation or chemical processes.

Sebacic acid (SA) is an aliphatic ten-carbon dicarboxylic acid (1,10-decanedioic acid) with a variety of industrial applications, including the production of plasticizers, lubricants, cosmetics, and plastics. Currently, SA is produced exclusively from alkaline pyrolysis of castor oil. Herein, we present an environmentally friendly green route of SA production from plant oil-derived sources by microbial ω-oxidation. We genetically engineered β-oxidation-blocked diploid yeast Candida tropicalis, and created an effective microbial cell factory with an increase of 46% in SA production by overexpression of genes involved in ω-oxidation of hydrocarbons compared to the original strain. A biotransformation process of SA production from decanoic acid methyl ester was developed to overcome the challenges of high-density cell culture, substrate feed, substrate/intermediate toxicity, and foam generation. Fed-batch production of engineered C. tropicalis resulted in a molar yield of above 98%, a productivity of 0.57 g L−1 h−1, and a final titre of 98.3 g L−1 in a 5-litre fermenter and the results were successfully reproduced using a larger scale 50-litre fermenter. The produced SAs were successfully purified to >99.8% using acid precipitation and recrystallization. Finally, bio-nylon 610 was successfully synthesized by polymerization of the purified SA with hexamethylenediamine and showed thermal properties very similar to those of commercially available nylon 610. The processes developed and described in this study can be employed to produce and isolate SA for the synthesis of bio-nylons, using environmentally friendly procedures based on microbial biotransformation with potential industrial applications.

Controlling the residual glucose concentration is important for improving productivity in L-threonine fermentation. In this study, we developed a procedure to automatically control the feeding quantity of glucose solution as a function of ammonia-water consumption rate. The feeding ratio (RC/N) of glucose and ammonia water was predetermined via a stoichiometric approach, on the basis of glucose-ammonia water consumption rates. In a 5-L fermenter, 102 g/l L-threonine was obtained using our glucose-ammonia water combined feeding strategy, which was then successfully applied in a 500-L fermenter (89 g/l). Therefore, we conclude that an automatic combination feeding strategy is suitable for improving L-threonine production.

Purpose To assess the effect of a preoperative virtual reality (VR) experience of 3-dimensional (3D) reconstructed magnetic resonance images (MRIs) on anxiety reduction in patients undergoing arthroscopic knee surgery. Methods Patients in the VR group watched a 3D model of their own MRI through a VR headset describing the anatomy of the knee as well as their own lesion of interest for an arthroscopic procedure. Patients in the non-VR (NR) group received standard preoperative information about their MRI. The primary outcome for analysis was the Amsterdam Preoperative Anxiety and Information Scale score to measure level of anxiety and the need for information in patients undergoing arthroscopic knee surgery. Secondary outcomes were rated with visual analog scale (VAS) scores measuring patient pain, preparedness, satisfaction, and stress. Results Regarding the Amsterdam Preoperative Anxiety and Information Scale score, the sum S (surgery-related anxiety) and sum C (combined anxiety component) subscales showed significantly better outcomes in the VR group (median [interquartile range] for sum S = 2.0 [2.0-4.0], median [quartile 1-quartile 3] sum C = 4.0 [4.0-8.5]) than in the NR group (median [interquartile range] for sum S = 4.9 [3.0-5.0], median [quartile 1-quartile 3] sum C = 8.0 [5.3-9.8]) (P = .014 and P = .005, respectively). Regarding VAS scores, preoperative measures showed significantly better outcomes in satisfaction among VR group patients (95 [90.0-100.0]) in comparison to NR group patients (85 [70.0-96.0]) (P = .010). For postoperative VAS measures, the VR group (satisfaction score = 95 [90.0-100.0], stress score = 15 [2.5-37.5]) showed significantly better outcomes in satisfaction and stress in comparison to the NR group (satisfaction score = 85 [70.0-97.5], stress score = 30 [30.0-50.0]). Conclusions Application of preoperative VR experience of 3D reconstructed knee MRIs in patients undergoing arthroscopic knee surgery reduces anxiety around surgical encounters. The VR patient group was more satisfied overall and less stressed postoperatively. However, perioperative pain and preparedness were not affected by VR exposure. Level of Evidence Level I, randomized controlled trial.

Controlling the residual glucose concentration is important for improving productivity in L-threonine fermentation. In this study, we developed a procedure to automatically control the feeding quantity of glucose solution as a function of ammonia-water consumption rate. The feeding ratio (R

In the course of a search for anti-inflammatory metabolites from marine-derived fungi, methylpenicinoline (1) was isolated from a marine isolate of Penicillin sp. Compound 1 inhibited lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production by suppressing the expression of inducible NO synthase (iNOS) in RAW264.7 macrophages and BV2 microglia. It also attenuated prostaglandin E2 (PGE2) production by suppressing cyclooxygenase-2 (COX-2) expression in a concentration-dependent manner (from 10 μM to 80 μM) without affecting cell viability. In addition, compound 1 reduced the production of the pro-inflammatory cytokine interleukin-1β (IL-1β). In a further study designed to elucidate the mechanism of its anti-inflammatory effects, compound 1 was shown to block nuclear factor-kappa B (NF-κB) activation in LPS-induced RAW264.7 macrophages and BV2 microglia by inhibiting the phosphorylation of inhibitor kappa B-α (IκB-α), thereby suppressing the nuclear translocation of NF-κB dimers, namely p50 and p65, that are known to be crucial molecules associated with iNOS and COX-2 expression. In addition, compound 1 inhibited the activation of mitogen-activated protein kinase (MAPK) pathways. Taken together, the results suggest that compound 1 might be a valuable therapeutic agent for the treatment of anti-inflammatory and anti-neuroinflammatory diseases.

It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors.

Objectives To evaluate the recurrence rate of ovarian fibroma/fibrothecoma and reproductive outcomes following ovarian-sparing local mass excision in premenopausal women. Study design A retrospective cohort study was performed at two gynecologic surgery centers using data collected between January 2005 and December 2011. It included premenopausal patients treated with ovarian-sparing local mass excision and pathologically proven ovarian fibroma/fibrothecoma who were followed up for at least 6 months. The recurrence of fibroma/fibrothecoma and pregnancy outcomes in those who wanted to conceive after local mass excision were collected and analyzed. Results The mean age of the patients (n = 50) was 33.3 ± 6.9 years (range, 20–50 years), and the mean follow-up duration was 26.6 ± 19.2 months (range, 6–88 months). Fibroma was present in 40 patients, fibrothecoma in 7, and cellular fibroma in 3. Natural conception occurred in 11 of the 12 patients who became pregnant during the follow-up period. On follow-up ultrasonography, one patient experienced recurrent disease, 50 months after initial surgery, resulting in a crude overall recurrence rate of only 2%. Conclusion Given the 2% recurrence rate of ovarian fibroma/fibrothecoma following ovarian sparing local mass excision, local mass excision appears to be an effective surgical option in women of reproductive age.