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Several superhigh dams (greater than 200 m in height) and many high dams have been built in the upper Yangtze River basin in recent years, and these dams have made total dissolved gas (TDG) supersaturation a serious environmental problem. A few studies have examined the tolerance and avoidance characteristics of rare and endemic fish in TDG‐supersaturated water in the upper Yangtze River over the past 10 years. These studies focused on specific species and specific sizes and did not identify a regular pattern that can be applied to all resident fish in the upper Yangtze River. However, elucidating this type of pattern is crucial for fishery management and dam operations in the upper Yangtze River. Data on the median lethal time (LT₅₀), horizontal avoidance percentage, and vertical water depth of three rare and endemic species in the upper Yangtze River from previous studies were used in the current work. An exponential relationship was found between LT₅₀ of fish and TDG supersaturation. The avoidance percentage of fish has a linear relationship with TDG supersaturation. Fish in the upper Yangtze River can use depth compensation to avoid the threat of TDG when the saturation is 130% or above but rarely avoid the threat of TDG when the saturation is less than 125%. We also described the tolerance and avoidance characteristics of fish in a TDG‐supersaturated river downstream from a super‐high dam. When the dam discharged a two‐year flood, the LT₅₀ values of fish downstream ranged from 9.1 to 27.5 hr regardless of depth compensation. The avoidance percentage of resident fish ranged from 8.4 to 44.8%. The resident fish swam to a water depth of 2.43–3.33 m to avoid the threat of TDG.

Magnetotactic bacteria (MTB) demonstrate photoresponse. However, little is known about the biological significance of this behaviour. Magnetosomes exhibit peroxidase-like activity and can scavenge reactive oxygen species (ROS). Magnetosomes extracted from the Magnetospirillum magneticum strain AMB-1 show enhanced peroxidase-like activity under illumination. The present study investigated the effects of light irradiation on nonmagnetic (without magnetosomes) and magnetic (with magnetosomes) AMB-1 cells. Results showed that light irradiation did not affect the growth of nonmagnetic and magnetic cells but significantly increased magnetosome synthesis and reduced intracellular ROS level in magnetic cells. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to analyse the expression level of magnetosome formation-associated genes (mamA, mms6, mms13 and mmsF) and stress-related genes (recA, oxyR, SOD, amb0664 and amb2684). Results showed that light irradiation upregulated the expression of mms6, mms13 and mmsF. Furthermore, light irradiation upregulated the expression of stress-related genes in nonmagnetic cells but downregulated them in magnetic cells. Additionally, magnetic cells exhibited stronger phototactic behaviour than nonmagnetic ones. These results suggested that light irradiation could heighten the ability of MTB to eliminate intracellular ROS and help them adapt to lighted environments. This phenomenon may be related to the enhanced peroxidase-like activity of magnetosomes under light irradiation.

Total dissolved gas (TDG) supersaturation is becoming an increasingly serious problem in the upper Yangtze River basin and has been identified as a potentially negative environmental effect of hydropower development and operations. Juvenile Rock Carp Procypris rabaudi and Prenant’s Schizothoracin Schizothorax prenanti dwell in the upper reaches of the Yangtze River and were selected as experimental fish to evaluate the impact of TDG supersaturation on swimming performance. The results showed that the swimming speeds of Rock Carp and Prenant’s Schizothoracin differed significantly under different exposure times to TDG-supersaturated water (129–131%). Exposure of fish to supersaturated TDG for 2 and 4 h with no recovery resulted in significantly lower critical swimming (Ucrit) and burst swimming (Uburst) speeds compared with those of fish not exposed to supersaturated TDG. The Ucrit and Uburst values for Rock Carp not exposed to supersaturated TDG were 1.4–1.6 times higher than those of fish exposed...

Objective No drug is yet approved to treat the core symptoms of autism spectrum disorder (ASD). Low-dose suramin was effective in the maternal immune activation and Fragile X mouse models of ASD. The Suramin Autism Treatment-1 (SAT-1) trial was a double-blind, placebo-controlled, translational pilot study to examine the safety and activity of low-dose suramin in children with ASD. Methods Ten male subjects with ASD, ages 5–14 years, were matched by age, IQ, and autism severity into five pairs, then randomized to receive a single, intravenous infusion of suramin (20 mg/kg) or saline. The primary outcomes were ADOS-2 comparison scores and Expressive One-Word Picture Vocabulary Test (EOWPVT). Secondary outcomes were the aberrant behavior checklist, autism treatment evaluation checklist, repetitive behavior questionnaire, and clinical global impression questionnaire. Results Blood levels of suramin were 12 ± 1.5 μmol/L (mean ± SD) at 2 days and 1.5 ± 0.5 μmol/L after 6 weeks. The terminal half-life was 14.7 ± 0.7 days. A self-limited, asymptomatic rash was seen, but there were no serious adverse events. ADOS-2 comparison scores improved by −1.6 ± 0.55 points (n = 5; 95% CI = −2.3 to −0.9; Cohen's d = 2.9; P = 0.0028) in the suramin group and did not change in the placebo group. EOWPVT scores did not change. Secondary outcomes also showed improvements in language, social interaction, and decreased restricted or repetitive behaviors. Interpretation The safety and activity of low-dose suramin showed promise as a novel approach to treatment of ASD in this small study.

Total dissolved gas (TDG) supersaturation on the upper Yangtze River basin is becoming increasingly serious because of the intense construction of high dams, posing a threat to resident fish. The tolerance and behavior characteristics of Rock Carp Procypris rabaudi preexposed to TDG-supersaturated water were evaluated by placing juveniles (weight 6.4 ± 1.67 g, fork length 7.2 ± 0.7 cm; mean ± SD) in 35-cm-deep tanks at 130% supersaturation for 2.33 h as preexposure. Surviving fish were allowed 5 d of recovery in saturated-equilibrium (100% TDG) water and then examined in an acute lethality experiment at TDG supersaturation values of 120, 125, 130, 135, 140, and 145%. The resulting median lethal times were 10.4, 4.6, 3.2, 2.1, 1.4, and 1.4 h, respectively. The preexposed fish showed a poorer tolerance to TDG-supersaturated water than did a control group that were not preexposed for TDG above 120% supersaturation (P < 0.05 in cases where there was a significant difference between individual groups)....

When water is allowed to spill over a hydroelectric dam, the intense aeration and pressure in the deep plunge-pool produced by the high-volume discharge generates water supersaturated with total dissolved gases (TDGs) in areas downstream from the dam, which can cause gas bubble disease (GBD) in fish and threaten their survival. Experiments were conducted to measure the acute lethality, intermittent exposure, horizontal avoidance, and vertical avoidance of Prenant's Schizothoracin Schizothorax prenanti related to TDG supersaturation. The fish were placed in different tanks containing TDG-supersaturated water at a maximum water depth of 35 cm, and the resulting median lethal times (LT50) determined for the fish were 23.88, 9.66, 8.74, 8.03, 4.61, 3.48, and 2.81 h when the TDG supersaturation levels were 120, 125, 130, 135, 140, 145, and 150%, respectively. The LT50 values of the fish in continuous exposure conditions were not significantly different from the LT50 values of fish subjected to intermit...

This review gives an overview of the recent developments and applications in the use of CE-mediated microanalysis for enzyme studies. The period covers mid-2011 until mid-2013. Both off-line and in-line enzyme assays with their applications using CE are described in this article. For the in-capillary enzyme reaction, the techniques using electrophoretically mediated microanalysis (EMMA) as well as immobilized enzyme reactor (IMER) are discussed. The applications include the evaluation of enzyme activity, enzyme kinetics, enzyme inhibition, screening of enzyme inhibitors, and the study of enzyme-mediated drug metabolism.

Tunable white light emission is obtained from γ-irradiated Ag/Eu co-doped 65NaPO3—30Al(PO3)3—5SiO2 phosphate glass under 320—394 nm excitation.