Rapid toxicity assessment of six antifouling booster biocides using a microplate-based chlorophyll fluorescence in Undaria pinnatifida gametophytes

Biocides of antifouling agents can cause problems in marine ecosystems by damaging to non-target algal species. Aquatic bioassays are important means of assessing the quality of water containing mixtures of contaminants and of providing a safety standard for water management in an ecological context. In this study, a rapid, sensitive and inexpensive test method was developed using free-living male and female gametophytes of the brown macroalga Undaria pinnatifida. A conventional fluorometer was employed to evaluate the acute (48 h) toxic effects of six antifouling biocides: 4,5-Dichloro-2-octyl-isothiazolone (DCOIT), diuron, irgarol, medetomidine, tolylfluanid, zinc pyrithione (ZnPT). The decreasing toxicity in male and female gametophytes as estimated by EC50 (effective concentration at which 50% inhibition occurs) values was: diuron (0.037 and 0.128 mg l(-1), respectively) > irgarol (0.096 and 0.172 mg l(-1), respectively) > tolylfluanid (0.238 and 1.028 mg l(-1), respectively) > DCOIT (1.015 and 0.890 mg l(-1), respectively) > medetomidine (12.032 and 12.763 mg l(-1), respectively). For ZnPT, 50% fluorescence inhibition of U. pinnatifida gametophytes occurred at concentrations above 0.4 mg l(-1). The Undaria method is rapid, simple, practical, and cost-effective for the detection of photosynthesis-inhibiting biocides, thus making a useful tool for testing the toxicity of antifouling agents in marine environments

Dietary behavior and its influencing factors among experienced shiftwork nurses: a secondary analysis

Purpose This study investigated the dietary behavior of experienced shiftwork nurses and aimed to identify factors related to dietary behavior. Methods This study was a secondary analysis based on the Shift Work Nurses’ Health and Turnover study (2018-2021) among Korean nurses. In total, 247 experienced (>12 months) shiftwork nurses were included in this study. The participants’ dietary behavior, depression, level of occupational stress, fatigue, physical activity, and general characteristics were measured. Descriptive statistics, Pearson correlation coefficients, independent t-test, one-way analysis of variance, the Kruskal-Wallis test, and multiple regression analysis were conducted. Results The dietary behavior score of the participants using the Mini-Dietary Assessment Index was 29.35±5.67. Thirty percent of the participants were depressed, the participants experienced moderate occupational stress, and 74.1% of the participants engaged in an inadequate amount of physical activity. The factors influencing shiftwork nurses’ dietary behavior were having child(ren) (β=.16, p=.027), depression (β=–.13, p=.032), level of occupational stress related to occupational climate (β=–.13, p=.035), and an inadequate amount of physical activity (β=–.17, p=.006). These factors explained 10.4% of the variance in experienced shiftwork nurses’ dietary behavior scores. Conclusion Experienced nurses with child(ren) tended to have healthier diets. However, a higher level of occupational stress related to occupational climate, depression, and engaging in an inadequate amount of physical activity were associated with a higher risk of having an unhealthy diet. Therefore, strategies are needed to encourage physical activity and alleviate adverse occupational climate and depression among experienced nurses

The involvement of GSK3β for glycogen synthesis throughout the annual cycle of Pacific oyster, Crassostrea gigas (Magallana gigas)

Crassostrea gigas is a frequently studied species in understanding physiological processes in bivalves. Similar to other animals, oysters store glucose in the body as glycogen. Glycogen is known to supply energy for germ cell development and maintenance. Glycogen is synthesized by glycogen synthase. GSK3β regulates glycogen synthase activity and plays an important role in glycogen synthesis. Therefore, this study aims to examine the effect of GSK3β on the annual cycle of oysters and the glycogen synthesis pathway and to investigate the energy pathway in comparison with seasonal variation. Oysters were sampled monthly for one year and were subjected to glycogen content, RT-PCR, FISH, and western blot analysis. The year-round glycogen content significantly differs only in the mantle edge during spring and summer of both sexes but not in labial palp, digestive gland, gonad, and adductor muscle. The expression of GSK3β mRNA level was highest in October for females and April for males. Both sexes had the lowest expression in July. In the adductor muscle, females and males showed the highest expression in April and the lowest in July and October. The pattern of GSK3β expression in gonads and adductor muscle was similarly confirmed through FISH. As a result of examining the signaling system, p-GSK3β (serine 9) increased. At the same time, glycogen synthase decreased in May when the condition index was the highest, p-GSK3β decreased in October and July when spawning occurred, and glycogen synthase increased. Overall, it is thought that p-GSK3β expression is high in C. gigas at ripe, which inhibits glycogen synthesis and is used as energy for growth and maturation. Glycogen synthesis occurs for energy storage during degeneration

A Case of Occupational Rhinitis Caused by Rice Powder in the Grain Industry

Rice is the major staple food in a large part of the world, especially in Asia. Hypersensitivity reactions to rice are rare. Moreover, cases of occupational allergies induced by inhalation of rice powder are uncommon. We report a 31-year-old male with work-related rhinitis and conjunctivitis symptoms caused by occupational exposure to rice powder in the grain industry. He showed positive responses to rice extracts on a skin prick test, and a high level of serum specific IgE to rice was detected by ELISA. Occupational rhinitis was confirmed by a nasal provocation test with rice extracts. An IgE ELISA inhibition test showed cross-creativity between rice and various grass pollen extracts. These findings suggest that the inhalation of rice powder can induce IgE-mediated occupational rhino-conjunctivitis, which may be derived from cross-reactivity to major grass pollens

Reappraisal of the toxicity test method using the green alga Ulva pertusa Kjellman (Chlorophyta),

This study was aimed to develop an objective way of quantifying the reproductive status of the green macroalga, Ulva pertusa using a vital stain and programmed automated analysis (by Image J program). The EC50 values (with 95% CI), the concentrations of toxicants inducing a reduction of 50% in sporulation after 96 h exposure, from the newly developed method were similar to those obtained by the conventional method: 0.651 (0.598-0.705) mg l(-1) for Cd, 0.144 (0.110-0.162) mg l(-1) for Cu, 0.180 (0.165-0.195) mg l(-1) for atrazine, 0.076 (0.049-0.094) mg l(-1) for diuron and 30.6 (26.5-34.4) ml l(-1) for DMSO, respectively. When the EC50 values from this study were compared to that those from literatures, the sensitivity for some toxicants was similar or higher than that of U. fasciata (1.930 mg l(-1) for germination for Cd), U. armoricana (0.250 mg l(-1) for Fv/Fm for Cu), U. reticulata (0.126-1.585 mg l(-1) for growth for Cu), and U. intestinalis (0.650 mg l(-1) for Fv/Fm for atrazine). The subjective views of the experimental performers can be eliminated using the newly developed method. The Ulva method gave consistent responses to Cu and Cd of internationally allowable ranges for effluents, implying that the method is a useful tool for monitoring industrial wastewaters containing these metals

Investigation on Health Effects of an Abandoned Metal Mine

To investigate potential health risks associated with exposure to metals from an abandoned metal mine, the authors studied people living near an abandoned mine (n=102) and control groups (n=149). Levels of cadmium, copper, arsenic, lead, and zinc were measured in the air, soil, drinking water, and agricultural products. To assess individual exposure, biomarkers of each metal in blood and urine were measured. β2-microglobulin, α1-microglobulin, and N-acetyl-beta-glucosaminidase and bone mineral density were measured. Surface soil in the study area showed 2-10 times higher levels of metals compared to that of the control area. Metal concentrations in the groundwater and air did not show any notable differences between groups. Mean concentrations of cadmium and copper in rice and barley from the study area were significantly higher than those of the control area (p<0.05). Geometric means of blood and urine cadmium in the study area were 2.9 µg/L and 1.5 µg/g Cr, respectively, significantly higher than those in the control area (p<0.05). There were no differences in the levels of urinary markers of early kidney dysfunction and bone mineral density. The authors conclude that the residents near the abandoned mine were exposed to higher levels of metals through various routes

Overexpression of cathepsin S exacerbates lupus pathogenesis through upregulation TLR7 and IFN-α in transgenic mice

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects multiple organs. Recent studies suggest relevance between cysteine protease cathepsin S (CTSS) expression and SLE. To investigate the mechanism of CTSS in SLE, CTSS-overexpressing transgenic (TG) mice were generated, and induced lupus-like symptoms. Eight months later, the TG mice spontaneously developed typical SLE symptoms regardless of the inducement. Furthermore, we observed increased toll-like receptor 7 (TLR7) expression with increased monocyte and neutrophil populations in the TG mice. In conclusion, overexpression of CTSS in mice influences TLR7 expression, autoantibodies and IFN-α, which leads to an autoimmune reaction and exacerbates lupus-like symptoms. © 2021, The Author(s).1

Toll-like receptor 2 downregulation and cytokine dysregulation predict mortality in patients with Staphylococcus aureus bacteremia

Background Staphylococcus aureus bacteremia (SAB) presents heterogeneously, owing to the differences in underlying host conditions and immune responses. Although Toll-like receptor 2 (TLR2) is important in recognizing S. aureus, its function during S. aureus infection remains controversial. We aimed to examine the association of TLR2 expression and associated cytokine responses with clinical SAB outcomes. Methods Patients from a prospective SAB cohort at two tertiary-care medical centers were enrolled. Blood was sampled at several timepoints (≤5 d, 6–9 d, 10–13 d, 14–19 d, and ≥ 20 d) after SAB onset. TLR2 mRNA levels were determined via real-time PCR and serum tumor necrosis factor [TNF]-α, interleukin [IL]-6, and IL-10 levels were analyzed with multiplex-high-sensitivity electrochemiluminescent ELISA. Results TLR2 levels varied among 59 SAB patients. On days 2–5, TLR2 levels were significantly higher in SAB survivors than in healthy controls (p = 0.040) and slightly but not significantly higher than non-survivors (p = 0.120), and SAB patients dying within 7 d had lower TLR2 levels than survivors (P = 0.077) although statistically insignificant. IL-6 and IL-10 levels were significantly higher in non-survivors than in survivors on days 2–5 post-bacteremia (P = 0.010 and P = 0.021, respectively), and those dying within 7 d of SAB (n = 3) displayed significantly higher IL-10/TNF-α ratios than the survivors did (P = 0.007). Conclusion TLR2 downregulation and IL-6 and IL-10 concentrations suggestive of immune dysregulation during early bacteremia may be associated with mortality from SAB. TLR2 expression levels and associated cytokine reactions during early-phase SAB may be potential prognostic factors in SAB, although larger studies are warranted.This study was supported by a research grant (13–2014-002) from Seoul National University Bundang Hospital (Seongnam, South Korea). The funder had no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript