miR-330 targeting BCO2 is involved in carotenoid metabolism to regulate skin pigmentation in rainbow trout (Oncorhynchus mykiss).

BACKGROUND: MicroRNAs (miRNAs) play a critical role in regulating skin pigmentation. As a key economic trait, skin color directly affects the market value of rainbow trout (Oncorhynchus mykiss), however, the regulatory mechanism of most miRNAs in fish skin color is still unclear. RESULTS: In this study, the full-length cDNA sequence of ß-carotene oxygenase 2 (BCO2, a key regulator of carotenoid metabolism) from the rainbow trout was obtained using rapid-amplification of cDNA ends (RACE) technology, and qRT-PCR was used to investigate the differential expression of miR-330 and BCO2 in 14 developmental stages and 13 tissues between wild-type rainbow trout (WTrt) and yellow mutant rainbow trout (YMrt). Additionally, the function of miR-330 was verified by overexpression and silencing in vitro and in vivo. The results showed that the complete cDNA sequence of BCO2 was 2057 bp with a 1707 bp ORF, encoding a 568 amino acid protein having a molecular weight of 64.07 kD. Sequence alignment revealed that higher conservation of BCO2 protein amongst fishes than amongst other vertebrates, which was further confirmed by phylogenetic analysis. The analysis of spatial and temporal expression patterns suggested that BCO2 and miR-330 were abundantly expressed from fertilized-stage to multi-cell as well as in the dorsal and ventral skin of WTrt and YMrt, and their expression patterns were opposite in most of the same periods and tissues. In vitro, luciferase reporter assay confirmed that BCO2 was a direct target of miR-330, and transfection of miR-330 mimics into rainbow trout liver cells resulted in a decrease in the expression of BCO2; conversely, miR-330 inhibitor had the opposite effect to the miR-330 mimics. In vivo, miR-330 agomir significantly decreased BCO2 expression in dorsal skin, tail fin, and liver. Furthermore, overexpression of miR-330 could suppress cell proliferation and induce apoptosis. CONCLUSION: Our results showed that miR-330 is involved in the regulation of skin pigmentation in rainbow trout by targeting BCO2 and shows its promise as a potential molecular target to assist the selection of rainbow trout with better skin color patterns.

The work behaviors of patients with allergic rhinitis (AR) during the autumn pollen season.

BACKGROUND: This study aims to analyze the work behaviors of patients with allergic rhinitis (AR) during the autumn pollen season, using a 2-week diary survey. METHODS: In this study, we recruited patients with seasonal allergic rhinitis (SAR) who were allergic to autumn pollen using an experience sampling method. All participants completed a 2-week survey using the WeChat app during the autumn pollen season (September 16, 2018 through to September 30, 2018). Collected data included participants' general characteristics, nasal symptoms, symptoms of insomnia, mood, and unethical work behaviors. RESULTS: The results showed that pollen concentration had a significant positive effect on the symptoms of rhinitis (P<0.001). Nasal symptoms had direct, positive effects on night-time insomnia (P<0.01) and a negative mood the next day (P<0.05). Insomnia positively affected a negative mood the next day (P<0.01), while negative mood exhibited a direct, positive effect on unethical work behaviors (P<0.05). Furthermore, pollen concentration, nasal symptoms, and insomnia were indirectly but positively associated with unethical work behaviors in patients with SAR. CONCLUSIONS: Nasal symptoms in patients with SAR were aggravated by pollen dispersion that induced a higher incidence of insomnia, which subsequently provoked a negative mood the next day. Therefore, the spillover effects of seasonal pollen included an increased incidence of unethical work behaviors.

Multivalency-assisted membrane-penetrating siRNA delivery sensitizes photothermal ablation via inhibition of tumor glycolysis metabolism.

The success of photothermal therapy (PTT) is often hampered by the thermo-resistance of tumor cells mediated by over-expressed heat shock proteins (HSPs). Herein, we developed a guanidine-rich, spherical helical polypeptide (DPP) with multivalency-assisted strong membrane penetrating capability, which mediated effective RNAi against tumor glycolysis metabolism to sensitize PTT. ICG was loaded into the internal cavity of DPP, and siRNA against pyruvate kinase M2 (siPKM2) was condensed by DPP to form positively charged nanocomplexes (NCs). The NCs were further coated with human serum albumin to enhance serum stability, prolong blood circulation, and improve tumor targeting. Due to its multivalent topology, DPP exhibited stronger membrane activity yet lower cytotoxicity than its linear analogue (LPP), thus enabling efficient PKM2 silencing in MCF-7 cells in vitro (~75%) and in vivo (~70%). The PKM2 silencing inhibited tumor glycolysis metabolism and further depleted the energy supply for HSPs production, thus overcoming the heat endurance of tumor cells to strengthen ICG-mediated photothermal ablation. Additionally, siPKM2-mediated energy depletion led to tumor cell starvation, which imparted synergistic anti-cancer effect with PTT. This study therefore provides a promising strategy for designing membrane-penetrating siRNA delivery materials, and it renders a unique RNAi-mediated anti-metabolic mechanism in sensitizing PTT and enabling starvation therapy.

Effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish (Pelteobagrus fulvidraco).

This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish (Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets (42% protein and 9% lipid) were formulated to contain graded levels of arginine (2.44%, 2.64%, 2.81%, 3.01% and 3.23% of diet), by supplementing L-Arginine HCl. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain (WG) and specific growth rate (SGR) in 2.64% and 2.81% groups were significantly higher than those in 3.23% group (P < 0.05). The feed conversation ratio (FCR) in 2.64%, 2.81% and 3.01% groups was significantly decreased when compared with 3.23% group. The protein efficiency ratio (PER) in 2.64% group was significantly higher than that in 2.44% and 3.23% groups (P < 0.05). The condition factor (CF) of fish was significantly higher in 2.81% group than that in 2.44% group (P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index (HSI), viscerosomatic index (VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein (TP), triglyceride (TG), glucose (GLU), urea nitrogen (UN) contents and aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities (P > 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group (P < 0.05). The results suggested that dietary arginine level at 2.81% could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23% arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet (6.45% of dietary protein) under current culture conditions.

Job demands, job resources and safety outcomes: The roles of emotional exhaustion and safety compliance.

The aim of this study was to assess the effectiveness of the job demands-resources (JD-R) model in explaining the relationship of job demands and resources with safety outcomes (i.e., workplace injuries and near-misses). We collected self-reported data from 670 crude oil production workers from three sub-companies of a major oilfield company in China. The results of a structural equation analysis indicated that job demands (psychological and physical demands) and job resources (decision latitude, supervisor support and coworker support) could affect emotional exhaustion and safety compliance, and thus influence the occurrence of injuries and near-misses. The implications of the present findings regarding both the JD-R model and occupational safety research were discussed.