The Effect of Estrogens,River Water,and Treated Wastewater on Vitellogenin Induction of Japanese Medaka1

Abstract: The objective of this study is to evaluate the effect of estrogens on fish endocrine disruption in river water and treated wastewater. Endogenous estrogen estrone (E1), 17β‐estradiol (E2), river water, and treated wastewater were used for exposure tests on male Japanese medaka. Vitellogenin induction in male medaka was regarded as the endpoint of endocrine disruption. The effective concentrations of E1 and E2 on vitellogenin induction in medaka were evaluated by breeding medaka for 14 days in tanks with various concentrations of E1 or E2. Vitellogenin induction increased with elapse of time during exposure, with higher estrogen concentrations causing greater vitellogenin induction. According to the test results, the lowest observed effect concentrations (LOECs) of E1 and E2 were estimated to be 31.6 and 5.0 ng/l, respectively; and the E2 equivalent (EEQ) LOEC value of E1 was 5.2 ng‐E2/l, derived by multiplying the relative potency of E1 by that of E2 as estimated in this study. In continuous exposure tests using river water or treated wastewater, the estrogenic activity, an index of total estrogenic potential measured by yeast screen assay and expressed as EEQ, varied widely during the exposure tests, and significant vitellogenin induction was observed after several days of high levels of estrogenic activity in water. Vitellogenin concentration tended to significantly increase if EEQ exceeded the level of 5 ng‐E2/l. The threshold value was substantially the same as the results for E1 and E2 exposure tests of medaka. Consequently, EEQ over 5 ng‐E2/l was revealed to have the potential to cause endocrine disruption of male medaka. As estrogenic activity exceeding 5 ng‐E2/l was observed in some rivers in Japan, total estrogenic potential needs to be further decreased at wastewater treatment plants to prevent fish endocrine disruption.     

Prediction of probability of fatality due to brain injury in traffic accidents

Abstract

Objective: Fatal brain injuries result from physiological changes in brain tissues, subsequent to primary damage caused by head impact. Although efforts have been made in past studies to estimate the probability of brain injury, none of them involved prediction of such physiological changes. The goal of this study was to evaluate the fatality prediction capability of a novel approach that predicts an increase in intracranial pressure (ICP) due to primary head injury to estimate the fatality rate using clinical data that correlate ICP with fatality rate.

Methods: A total of 12 sets of head acceleration time histories were used to represent no, severe, and fatal brain injury. They were obtained from the literature presenting head kinematics data in noninjurious volunteer sled tests or from accident reconstruction for severe and fatal injury cases. These were first applied to a Global Human Body Models Consortium (GHBMC) head–brain model to predict nodal displacement time histories of the brain, which were then fed into FEBio to predict ICP. A Weibull distribution was applied to the data for the relationship between fatality rate and ICP obtained from a clinical paper to estimate fatality rate from ICP (procedure A). Fatality rate was also estimated by applying the temporal and spatial maximum value of maximum principal strain (MPS_max) obtained from the GHBMC simulation to an injury probability function for MPS_max (procedure B). Estimated fatality rates were compared between the 2 procedures.

Results: Both procedures estimated higher average fatality rate for higher injury severity. The average fatality rate for procedure A without ischemia representation and procedure B was 72.4 and 51.0% for the fatal injury group and 8.2 and 21.7% for the severe injury group, respectively, showing that procedure A provides more distinct classification between fatal and nonfatal brain injury. It was also found that representation of ischemia in procedure A provides results sensitive to injury severity and impact conditions, requiring further validation of the initial estimate for the relationship between brain compression and ischemic cell death.

Conclusions: Prediction of the probability of fatality by means of a combination of simulations of the primary brain deformation and subsequent ICP increase was found to be more distinct compared to the prediction of primary injury alone combined with the injury probability function from a past study in the select 12 head impact cases.     

Fluorescence immunoassay using an optical fiber for determination of Dermatophagoides farinae (Der f1)

Immunoassay methods are generally used for measuring of allergenic substances. However, they need special facilities, skilled handling, and time-consuming procedure. In this work, a fiber-optic immunoassay system which could measure allergen by fluorescent intensities of immune complexes formed by allergens and fluorescently labeled antibodies was established. Immune complexes absorbed on the optical fiber probe surface, and excitation light was injected into the probe, then evanescent field is created in the proximity of the probe. The fluorophores were excited by the evanescent light, and fluorescence was detected by a photo diode. The target allergen detected by our system was Der f1 derived from Dermatophagoides farinae that is one of the house dust mite and major source of inhaled allergens. The fluorophore used labeling on detecting antibody was cyanine 5. The system enabled to detect and quantitatively determine of Der f1. The measurement range was from 0.24 to 250?ng/ml, and the result competes with ELISA. The measurement time was 16?min/sample. The immunoassay system was applied to measurement of Der f1 from actual dust samples. Calculated values of Der f1 showed good correlations between the fiber-optic fluoroimmunoassay and ELISA.     

Recent advances in ionic liquids-based hybrid processes for CO2 capture and utilization

CO₂ capture and utilization (CCU) is an effective strategy to mitigate global warming. Absorption, adsorption and membranes are methods used for CO₂ separation and capture, and various catalytic pathways have also been developed for CO₂ utilization. Although widely researched and used in industry, these processes are energy-intensive and this challenge needs to be overcome. To realize further optimization, novel materials and processes are continuously being developed. New generation materials such as ionic liquids (ILs) have shown promising potential for cost-effective CO₂ capture and utilization. This study reviews the current status of ILs-based solvents, adsorbents, membranes, catalysts and their hybrid processes for CO₂ capture and utilization. The special properties of ILs are integrated into new materials through hybridization, which significantly improves the performance in the process of CCU.     

Fate estimation of estrogenic substances in an urban river by flux calculation.

This study investigated the fate of estrogenic substances in an urban river receiving discharge from wastewater treatment plants (WTPs) by flux calculation, focusing on the middle reaches of the Tama River in Tokyo, which is one of the most urbanized rivers in Japan. The level of estrogenic activity flux was almost negligibly small at the upstream station. The level was considerably raised after inflows from the WTPs and then the level declined in the lower reaches of the river. When contributions of estrogenic substances to estrogenic activity were estimated, estrone (E1) was the primary contributor to the total estrogenic activity in all the sampling stations, followed by estradiol (E2). The contribution of nonylphenol to estrogenic activity was small. The E1 and E2 accounted for approximately 90% or more of estrogenic activity in the Tama River. As for the total fluxes of the estrogenic substances in the study area in the Tama River, the proportion of flux associated with WTP discharge was approximately 100% of the total fluxes, and the effects of the tributaries flowing into the river were almost negligible. When the reduction ratios of estrogenic activity were calculated by the flux, the ratios were found to increase toward the lower reaches of the river. Similar changes were observed for E1. Meanwhile, the change of reduction ratios for E2 was different from that observed for estrogenic activity.     

A new class of mealybug pheromones: a hemiterpene ester in the sex pheromone of Crisicoccus matsumotoi

Mealybugs, which include several agricultural pests, are small sap feeders covered with a powdery wax. They exhibit clear sexual dimorphism; males are winged but fragile and short lived, whereas females are windless and less mobile. Thus, sex pheromones emitted by females facilitate copulation and reproduction by serving as a key navigation tool for males. Although the structures of the hitherto known mealybug pheromones vary among species, they have a common structural motif; they are carboxylic esters of monoterpene alcohols with irregular non-head-to-tail linkages. However, in the present study, we isolated from the Matsumoto mealybug, Crisicoccus matsumotoi (Siraiwa), a pheromone with a completely different structure. Using gas chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy, we identified the pheromone as 3-methyl-3-butenyl 5-methylhexanoate. Its attractiveness to males was confirmed in a series of field trapping experiments involving comparison between the isolated natural product and a synthetic sample. This is the first report of a hemiterpene mealybug pheromone. In addition, the acid moiety (5-methylhexanoate) appears to be rare in insect pheromones.