Lipid and fatty acid compositions of a novel docosahexaenoic acid-producing marine bacterium

An unidentified bacterial strain, SCRC-21406, isolated from the intestine of a marine fish, Glossanodon semifasciatus, produced docosahexaenoic acid at 23% (mol/mol) [=28% (w/w)] of total fatty acids in a medium containing 0.5% (wt/vol) peptone and 0.1% (wt/vol) yeast extract at 12°C under atmospheric pressure. The cell yield was 0.43 g/L. The major lipids of the strain were phosphatidylethanolamine and phophatidylglycerol. Docosahexaenoic acid was localized at the sn-2 positions of both phospholipids. The amounts of polyunsaturated fatty acids other than docosahexaenoic acid were extremely small [<3% (mol/mol)]. Monousaturated fatty acids of the cis-7, cis-9 and cis-11 types were detected.     

Droplet‐Shooting and Size‐Filtration (DSSF) Method for Synthesis of Cell‐Sized Liposomes with Controlled Lipid Compositions

We report a centrifugal microfluidic method, droplet‐shooting and size‐filtration (DSSF), for the production of cell‐sized liposomes with controlled lipid compositions. This involves the generation of large and small droplets from the tip of a glass capillary and the selective transfer of small droplets through an oil‐water interface, thus resulting in the generation of cell‐sized liposomes. We demonstrate control of the microdomain formation as well as the formation of asymmetric lipid bilayer liposomes of uniform size by the control of lipid composition. The DSSF method involves simple microfluidics and is easy to use. In addition, only a small volume (0.5–2 μL) of sample solution is required for the formation of hundreds of cell‐sized liposomes. We believe that this method can be applied to generate cell‐sized liposomes for a wide variety of uses, such as the construction of artificial cell‐like systems.     

Expression and Prognostic Significance of CD47–SIRPA Macrophage Checkpoint Molecules in Colorectal Cancer

Despite the confirmed anti-cancer effects of T-cell immune checkpoint inhibitors, in colorectal cancer (CRC) they are only effective in a small subset of patients with microsatellite-unstable tumors. Thus, therapeutics targeting other types of CRCs or tumors refractory to T-cell checkpoint inhibitors are desired. The binding of aberrantly expressed CD47 on tumor cells to signal regulatory protein-alpha (SIRPA) on macrophages allows tumor cells to evade immune destruction. Based on these observations, drugs targeting the macrophage checkpoint have been developed with the expectation of anti-cancer effects against T-cell immune checkpoint inhibitor-refractory tumors. In the present study, 269 primary CRCs were evaluated immunohistochemically for CD47, SIRPA, CD68, and CD163 expression to assess their predictive utility and the applicability of CD47–SIRPA axis-modulating drugs. Thirty-five percent of the lesions (95/269) displayed CD47 expression on the cytomembrane of CRC cells. CRCs contained various numbers of tumor-associated immune cells (TAIs) with SIRPA, CD68, or CD163 expression. The log-rank test revealed that patients with CD47-positive CRCs had significantly worse survival than CD47-negative patients. Multivariate Cox hazards regression analysis identified tubular-forming histology (hazard ratio (R) = 0.23), age < 70 years (HR = 0.48), and high SIRPA-positive TAI counts (HR = 0.55) as potential favorable factors. High tumor CD47 expression (HR = 1.75), lymph node metastasis (HR = 2.26), and peritoneal metastasis (HR = 5.80) were cited as potential independent risk factors. Based on our observations, CD47–SIRPA pathway-modulating therapies may be effective in patients with CRC.     

Single Cell Gene Expression Analysis in a 3D Microtissue Liver Model Reveals Cell Type-Specific Responses to Pro-Fibrotic TGF-β1 Stimulation

3D cell culture systems are widely used to study disease mechanisms and therapeutic interventions. Multicellular liver microtissues (MTs) comprising HepaRG, hTERT-HSC and THP-1 maintain multicellular interactions and physiological properties required to mimic liver fibrosis. However, the inherent complexity of multicellular 3D-systems often hinders the discrimination of cell type specific responses. Here, we aimed at applying single cell sequencing (scRNA-seq) to discern the molecular responses of cells involved in the development of fibrosis elicited by TGF-β1. To obtain single cell suspensions from the MTs, an enzymatic dissociation method was optimized. Isolated cells showed good viability, could be re-plated and cultured in 2D, and expressed specific markers determined by scRNA-seq, qRT-PCR, ELISA and immunostaining. The three cell populations were successfully clustered using supervised and unsupervised methods based on scRNA-seq data. TGF-β1 led to a fibrotic phenotype in the MTs, detected as decreased albumin and increased αSMA expression. Cell-type specific responses to the treatment were identified for each of the three cell types. They included HepaRG damage characterized by a decrease in cellular metabolism, prototypical inflammatory responses in THP-1s and extracellular matrix remodeling in hTERT-HSCs. Furthermore, we identified novel cell-specific putative fibrosis markers in hTERT-HSC (COL15A1), and THP-1 (ALOX5AP and LAPTM5).     

Suppressive effect of neoxanthin on the differentiation of 3T3-L1 adipose cells

The objective of this study was to assess the suppressive effects of 13 naturally occurring carotenoids on the adipocyte differentiation of 3T3-L1. The relationship between carotenoid structure and suppressive effects was also examined. Treatment with neoxanthin significantly reduced lipid accumulation, as well as glycerol-3-phosphate dehydrogenase activity. This suppressive effect on adipose cell differentiation was not observed in the other 12 carotenoids used in this study. Neoxanthin treatment also decreased expression of CCAAT/enhancer binding protein alpha (C/EBPalpha) and peroxisome proliferator-activated receptor gamma (PPARgamma) mRNAs. An examination of structure and function suggested that carotenoids containing an allene bond and an additional hydroxyl substituent on the side group may show suppressive effects on adipocyte differentiation in 3T3-L1 cells.     

Suppression of Noble Metal Sintering Based on the Support Anchoring Effect and its Application in Automotive Three-Way Catalysis

Suppression of noble metal sintering is a very important approach in the development of automotive three-way catalysts. The investigation into the Pt sintering behavior revealed that the formed Pt–O–M (M: cation of oxide, i.e., cerium oxide) bond acted as an anchor to suppress the Pt sintering, and that the strength of the Pt-oxide-support interaction was well correlated with the electron density of oxygen in the support oxide. To achieve a good balance between catalytic activity and the sintering suppression, ceria based oxide support was verified to be suitable for Pt, and zirconia based oxide support was appropriate support for Rh. Through optimizing the configuration of Pt and Rh in the catalyst, a novel three-way catalyst was developed successfully, and this catalytic activity is far superior to the conventional catalyst, but with lower noble metal content.     

Investigation of optimum electrode locations by using an automatized surface electromyography analysis technique.

Identification of the innervation zone is widely used to optimize the accuracy and precision of noninvasive surface electromyography (EMG) signals because the EMG signal is strongly influenced by innervation zones. However, simply structured fusiform muscle, such as biceps brachii muscle, has been employed mainly due to the simplicity with which the propagation from raw EMG signals can be observed. In this study, the optimum electrode location (OEL), free from innervational influence, was investigated by the propagation pattern of action potentials for brachii muscles and more complicated deltoid muscle structures using an automatized signal analysis technique. The technique employed newly developed computer software with additional clinical uses and minimized subjective differences. EMG signals were recorded using surface array electrodes during voluntary isometric contractions obtained from 12 healthy male subjects. Peaks in EMG signals were detected and averaged for each muscle. The propagation patterns and OEL were examined from biceps brachii muscles for all subjects and from deltoid muscles for seven subjects. The estimated locations were partially confirmed by comparing the root mean squares of the EMG signals. These results show that propagation patterns and OEL could be estimated simply and automatically even from the surface EMG signals of deltoid muscles.     

Identification and Biosynthesis of New Acyloins from the Thermophilic Bacterium Thermosporothrix hazakensis SK20‐1T

Two new acyloin compounds were isolated from the thermophilic bacterium Thermosporothrix hazakensis SK20‐1^T. Genome sequencing of the bacterium and biochemical studies identified the thiamine diphosphate (TPP)‐dependent enzyme Thzk0150, which is involved in the formation of acyloin. Through extensive analysis of the Thzk0150‐catalyzed reaction products, we propose a putative reaction mechanism involving two substrates: 4‐methyl‐2‐oxovalerate as an acyl donor and phenyl pyruvate as an acyl acceptor.