IL-6-Mediated Upregulated miRNAs in Extracellular Vesicles Derived from Lund Human Mesencephalic (LUHMES) Cells: Effects on Astrocytes and Microglia.

Psychological stress plays a major role in depression, and interleukin-6 (IL-6) is elevated during depression and psychological stress. MicroRNAs (miRNAs) in extracellular vesicles (EVs), including exosomes and microvesicles, suppress mRNA expression in other cells when endocytosed. In this study, we analyzed the effect of IL-6 on EVs secreted by neural precursor cells. Cells from the human immortalized neural precursor cell line LUHMES were treated with IL-6. EVs were collected using a nanofiltration method. We then analyzed the uptake of LUHMES-derived EVs by astrocytes (ACs) and microglia (MG). Microarray analysis of miRNAs was performed using EV-incorporated RNA and intracellular RNA from ACs and MG to search for increased numbers of miRNAs. We applied the miRNAs to ACs and MG, and examined the cells for suppressed mRNAs. IL-6 increased several miRNAs in the EVs. Three of these miRNAs were originally low in ACs and MG (hsa-miR-135a-3p, hsa-miR-6790-3p, and hsa-miR-11399). In ACs and MG, hsa-miR-6790-3p and hsa-miR-11399 suppressed four mRNAs involved in nerve regeneration (NREP, KCTD12, LLPH, and CTNND1). IL-6 altered the types of miRNAs in EVs derived from neural precursor cells, by which mRNAs involved in nerve regeneration were decreased in ACs and MG. These findings provide new insights into the involvement of IL-6 in stress and depression.

Nitrogen removal from wastewater by an immobilized consortium of microalgae-bacteria in hybrid hydrogels.

The high content of nitrogen in wastewater brings some operational, technical, and economical issues in conventional technologies. The aim of this study was to evaluate the nitrogen removal by hybrid hydrogels containing consortium microalgae-nitrifying bacteria in the presence of activated carbon (AC) used as an adsorbent of inhibitory substances. Hybrid hydrogels were synthesized from polyvinyl alcohol (PVA), sodium alginate (SA), biomass (microalgae-nitrifying bacteria), and AC. The hybrid hydrogels were evaluated based on the change in ammonium (NH4), nitrate (NO3), and chemical demand of oxygen (COD) concentrations, nitrification rate, and other parameters during 72 h. Results indicated that NH4 removal was more effective for hydrogels without AC than with AC, without significant differences regarding consortium biomass concentration (5 or 16%), presenting final concentrations of 3.13 and 3.75 mg NH4/L for hydrogels with 5 and 16% of the biomass, respectively. Regarding NO3 production, hydrogels without AC reached concentrations of 25.9 and 39.77 mg NO3/L for 5 and 16% of the biomass, respectively, while treatments with AC ended with 2.17 and 1.37 mg NO3/L. This confirms that hydrogels can carry out the nitrification process and do not need AC to remove potential inhibitors. The best performance was observed for the hydrogel with 5% of biomass without AC with a nitrification rate of 0.43 mg N/g TSS·h.

Mitigation of heat strain by wearing a long-sleeve fan-attached jacket in a hot or humid environment.

OBJECTIVES: This study examined whether a fan-attached jacket (FAJ) may mitigate the heat strain in hot or humid environment. METHODS: Nine healthy men engaged in 60-min sessions on a bicycle ergometer (4 metabolic equivalents [METs] workload) in hot-dry (40°C and 30% relative humidity) and warm-humid (30°C and 85% relative humidity) environments. Both are equivalent to an approximately 29°C wet-bulb globe temperature. The experiment was repeated-once wearing an ordinal jacket (control condition) and once wearing a long-sleeve FAJ that transfers ambient air at a flow rate of 12 L/s (FAJ condition)-in both environments. RESULTS: Increases in core temperatures in hot-dry environment were not statistically different between control and FAJ; however, that in the warm-humid environment were significantly different between control and FAJ (0.96 ± 0.10°C and 0.71 ± 0.11°C in rectal temperature, P < .0001; and 0.94 ± 0.09°C and 0.61 ± 0.09°C in esophageal temperature, P < .0001). Changes in heart rate were different between control and FAJ in both environments (62 ± 3 bpm and 47 ± 7 bpm, P < .0001 in hot-dry environment; and 61 ± 3 bpm and 46 ± 5 bpm, P < .0001 in the warm-humid environment) and decrease of %weight change was different in hot-dry environment (1.59 ± 0.12% and 1.25 ± 0.05%, P = .0039), but not in the warm-humid environment. CONCLUSIONS: Wearing a FAJ may mitigate heat strain both in hot or humid environments.

Advanced light-tolerant microalgae-nitrifying bacteria consortia for stable ammonia removal under strong light irradiation using light-shielding hydrogel.

The consortium of microalgae and nitrifying bacteria has attracted attention owing to its advantages, such as energy- and cost-efficiency in terms of using only light irradiation without aeration. However, high light intensity can easily cause photoinhibition of nitrifying bacteria, resulting in process breakdown of the consortium. This challenge limits its practical application in outdoor environment. In a previous study, we developed a "light-shielding hydrogel" which entrapped nitrifying bacteria in carbon black-added alginate hydrogel beads and confirmed its effectiveness of protecting the nitrifying bacteria from intense light up to 1600 µmol photons m-2 s-1. However, the applicability of the light-shielding hydrogel to microalgae-nitrifying bacteria consortia under strong light irradiation has not yet been clarified. In this study, we aimed to establish consortia of Chlorella sorokiniana and nitrifying bacteria immobilised in light-shielding hydrogel and evaluate their nitrification performance under strong light. Three nitrifying bacteria conditions were used: light-shielding hydrogel, hydrogel containing only nitrifying bacteria without carbon black ('hydrogel'), and dispersed nitrifier without immobilisation ('dispersion') as a control. At 1600 µmol photons m-2 s-1, the dispersion afforded a significant decrease in nitrification activity and subsequent process breakdown. In contrast, light-shielding hydrogel achieved complete nitrification without nitrite accumulation and had nitrification rates of approximately nine and two times higher than those for the dispersion and hydrogel conditions, respectively. Based on the overall evaluation, a possible sequence of process breakdown under strong light was also proposed. This study demonstrated for the first time that the light-shielding hydrogel/consortia combination had potential for applications, which require mitigation of photoinhibition under strong light irradiation. Further, it is expected that the proposed method will contribute to realise the practical application of microalgae-nitrifying bacteria consortia in various countries that experience high sunlight intensity due to their location in the sunbelt areas.