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Lipid-rich microalgae are a potential source for the bio-oil production. We isolated a novel oleaginous Thraustochytrid microalga from seawater, Schizochytrium sp. ABC101, and tested the effect of different growth conditions on its production of lipids. Batch fermentation experiments indicated that depletion of nitrogen led to lipid accumulation, and lipid accumulation led to increased cell size and decreased cell wall thickness. Based on these results, we tested three types of fed-batch fermentations (carbon and no nitrogen feeding, carbon and limited nitrogen feeding, carbon and sufficient nitrogen feeding) to examine the effect of adjusting the nitrogen supply on lipid accumulation. The limited nitrogen feeding provided the most efficient lipid production, with maxima after 60 h (dry cell weight [DCW]: 64.7 g/L, lipids: 25.4 g/L, docosahexaenoic acid [DHA]: 11.0 g/L). Use of corn steep liquor (CSL) as the sole nitrogen source also led to excellent performance, with maxima at 84 h (DCW: 86.0 g/L, lipids: 37.2 g/L, DHA: 16.7 g/L). In addition, use of CSL rather than yeast extract reduced the lipid production cost by 50%. Our results suggest that regulation of the nitrogen source improves the efficiency of microalgal lipid production and use of a low-cost nitrogen source reduces production costs.

The translucent white-coloured, Gram-stain-negative, aerobic, non-motile, fusiform-shaped bacterium (designated strain SY72T) was isolated from waste-activated sludge. Optimal growth occurred at 30–37 °C and pH 6.0–7.0. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the novel isolate belonged to the family Rhodobacteraceae of the class Alphaproteobacteria . Strain SY72T is closely related to Tabrizicola aquatica KCTC 23724T (97.8 % 16S rRNA gene sequence similarity) and Pseudorhodobacter aquaticus DC2N1-10T (96.4 %), respectively. DNA–DNA relatedness between strain SY72T and the closest phylogenetically related strain, Tabrizicola aquatica KCTC 23724T, was 18.0±0.7 %. In strain SY72T, the predominant respiratory quinone was ubiquinone Q-10, and the cellular fatty acids consisted mainly of C18 : 1ω7c and C18 : 1ω7c-11 methyl. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. Photoautotrophic and photoheterotrophic growth did not occur in strain SY72T. Furthermore, strain SY72T did not produce photosynthetic pigments or contain the photosynthetic genes pufL and pufM, by which it differed from the phototrophic species of the family Rhodobacteraceae . On the basis of distinct phenotypic and phylogenetic properties, strain SY72T represents a novel species of the genus Tabrizicola , for which the name Tabrizicola fusiformis sp. nov. is proposed. The type strain is SY72T (=KCTC 62105T=NBRC 113021T).

We isolated and characterized an oleaginous Thraustochytrid microalga. Based on 18 s rRNA sequencing, we classified this strain as Schizochytrium sp. SH103. Growth of these cells in a 5 L fermentor with a microbubble-type sparger (MTS) efficiently increased the oxygen transfer coefficient (OTC), while inducing only low external stress. For fermentation under conditions of low agitation (100 rpm) and aeration (3 L/min), the OTC was 8.6-fold higher using a MTS than a general type sparger (GTS). Under these same conditions, dry cell weight (DCW) productivity (0.54 vs. 1.26 g/L·h) and total lipid productivity (0.29 vs. 0.61 g/L·h) were each about 2.2-fold higher using a MTS than a GTS. Under conditions that optimized the OTC in a MTS fermentor (876 h−1), DCW productivity, total lipid productivity and DHA productivity were each 1.3-fold greater than non-optimized condition. Fed-batch fermentation experiments indicated the maximal DCW was 100.6 g/L at 48 h, maximal DCW productivity was 2.1 g/L·h, maximal lipid content was 48.6 g/L at 48 h, and lipid productivity was 1.0 g/L·h. Additionally, the results of experiments using a 50 L MTS fermentor (96.0 g/L DCW and 44.3 g/L total lipids at 48 h) were similar to those using the 5 L fermentor. Our results suggest that use of a MTS may help to achieve the efficient fermentation of heterotrophic microalgae for high cell densities.

We develop a dispatching policy for stochastic scheduling simulation especially for a continuous manufacturing system with machine breakdowns. The proposed dispatching policy computes an urgency index with the consideration of re-heating, setup cost and remaining due date. Prioritized by the index, we execute swapping or reassigning material sequences so as to minimize the total penalty cost. To evaluate the performance of the proposed policy, a discrete event simulation is developed. With 200 data sets and 20 iterations, we compare the performance of the urgency policy with those of SPT (Shortest Processing Time) and FCFS (First Come First Serve) which are the most common policies. The result shows that the proposed policy consistently gives the lowest total costs by reducing the penalty costs for lateness.

Background/Aims: To investigate the rate of detection of monosodium urate (MSU) crystals in the synovial fluid (SF) of patients with acute gouty arthritis and factors associated with false-negative results. Methods: A total of 179 patients with acute gouty arthritis who had undergone SF crystal examination were identified from the data warehouse of two university hospitals. Clinical and laboratory data were obtained from the medical records. Results: The overall rate of detection of MSU crystals was 78.8%. In univariate analyses, the only significant differences between the variables of crystal-negative and crystal-positive patients were a lower C-reactive protein level (p = 0.040) and fewer patients undergoing emergent surgery in the crystal-positive group (p = 4.5 × 10-6). In logistic regression analyses, MSU crystal-negative results were significantly associated with the interval from arthritis onset to crystal examination (p = 0.042), and this was the most significant risk factor for arthroscopic surgery (p = 2.1 × 10-4). Seventeen patients who underwent arthroscopic surgery had a significantly longer hospital stay (p = 0.007) and a significant delay in gout treatment (p = 8.74 × 10-5). The distribution of crystal-negative patients differed significantly between the SF samples that were evaluated by both the laboratory medicine and the rheumatology departments (p = 1.2 × 10-14), and the κ value was 0.108. Conclusions: Although several clinical features were associated with detection failure, SF MSU crystal identification was critically dependent on the observer. Considering the impact on the treatment outcomes, implementation of a quality control program is essential.

Relapsing polychondritis is an episodic, systemic inflammation of the cartilage with unknown autoimmune etiology. It leads to the destruction of cartilaginous structures of the ear, eye, nose, respiratory tract, joints, skin, and heart valve, and its presented symptoms are diverse. It can be improved mainly by corticosteroid or immunosuppressive agents. Recently, the use of biologic agents (TNF inhibitors, rituximab, tocilizumab et al) was reported from abroad. However, there is no reported case of relapsing polychondritis, which is treated by biologic agents in Korea. We report this first case of refractory relapsing polychondritis, which was improved with a treatment of Infliximab.

Objective. To assess the efficacy and safety of rituximab (RTX) on disease activity and muscle strength in patients with inflammatory myopathies refractory to conventional therapy. Methods. Four inflammatory myopathy patients who had been refractory to glucocorticoids, one or more immunosuppressive therapies and intravenous immunoglobulin were treated on an open-label basis. Each patient received two 500 mg doses of RTX 2 weeks apart in one cycle. In one patient who did not respond after the first cycle of RTX, the infusion schedule was modified by the physician. We measured muscle enzyme including CPK, LDH and assessed muscle strength individually to evaluate RTX response. Additionally anti-CD19 antibody was measured. Results. Three patients responded to the first cycle of RTX treatment with improvements in muscle enzyme and muscle strength, and then maintained physical function over the duration of several infusion cycles. In one patient, muscle enzyme did not decrease after the first cycle of RTX, and a high dose glucocorticoid was given. After modifying the treatment schedule with monthly RTX infusion, his muscle enzyme level and muscle strength improved. Anti-CD19 antibody decreased after RTX generally, but responses were variable. Herpes zoster infection occurred in two patients. Conclusion. Rituximab may be a therapeutic choice in refractory inflammatory myopathy. However a further trial is needed to confirm the efficacy and prove the safety.