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Use of the moribund state as an endpoint for acute toxicity testing in fish is complicated by the lack of consensus about the sublethal signs that define the state or that can predict imminent death. Defining the moribund state in fish requires determination of the association between each observable sublethal sign and transition to imminent death. To establish a criterion for defining the moribund state in Japanese medaka (Oryzias latipes), we determined death/clinical-sign ratios, defined as the proportion of fish with each clinical sign that transitioned to imminent death, for 13 clinical signs observed in individually housed fish exposed to one of two typical toxicants, three pharmaceuticals, two pesticides, and one metal. Also, the time from onset of each clinical sign to transition to imminent death (referred to as the survival time) was determined by continuous monitoring. Three of the observed clinical signs-immobility, lethargy, and immobility at the surface-were found to be indicators of the moribund state, with each of these signs having a death/clinical-sign ratio of 1.0. Evaluation of the survival time after onset of the other 10 signs enabled determination of whether timely euthanasia would be appropriate, thereby providing a means of reducing the suffering of laboratory fish in the period before death. Environ Toxicol Chem 2022;41:1089-1095. © 2022 SETAC.

Dependence on a partner facilitates various types of relationship maintenance effort. In this paper, we report on two experiments in which the level of dependence was manipulated. Study 1 tested whether dependence promotes other enhancement (a form of ingratiation, whereby the likeability of the partner is positively distorted). Study 2 tested whether dependence amplifies a sense of guilt after inadvertently committing a mild form of transgression against the partner, and whether amplified guilt facilitates self-punishment. In both experiments, dependence was manipulated in a conceptually similar manner: Participants' experimental rewards were partially determined by their partner's decision. Dependence promoted other enhancement (Study 1) but did not amplify guilt, and failed to promote self-punishment (Study 2). Possible reasons for the contradictory findings of the two studies are discussed.

A previous systematic review revealed that lutein intake leads to improved cognitive function among older adults. However, the association between lutein intake and brain health remains unclear. Methods: We searched the Web of Science, PubMed, PsycInfo, and Cochrane Library for research papers. The criteria were (1) an intervention study using oral lutein intake or a cross-sectional study that examined lutein levels and the brain, (2) participants were older adults, and (3) brain activities or structures were measured using a brain imaging technique (magnetic resonance imaging (MRI) or electroencephalography (EEG)). Results: Seven studies using MRI (brain activities during rest, cognitive tasks, and brain structure) and two studies using EEG were included. We mainly focused on MRI studies. Three intervention studies using MRI indicated that 10 mg lutein intake over 12 months had a positive impact on healthy older adults’ brain activities during learning, resting-state connectivity, and gray matter volumes. Four cross-sectional studies using MRI suggested that lutein was positively associated with brain structure and neural efficiency during cognitive tasks. Conclusion: Although only nine studies that used similar datasets were reviewed, this systematic review indicates that lutein has beneficial effects on healthy older adults’ brain health.

Diclofenac sodium, a non-steroidal anti-inflammatory drug widely used in both human and veterinary medicine, has been detected in aquatic environments; therefore, its ecotoxicological effects on aquatic organisms need to be clarified. Recently, toxicity testing using zebrafish (Danio rerio) embryos has been recommended from the point of view of animal welfare; therefore, we investigated the suitability of using sub-lethal endpoints observed during embryogenesis for predicting lethal effects in early life stage zebrafish exposed to diclofenac sodium. After exposure to diclofenac sodium (0.4-7.0 mg/L) from 2 hours post-fertilization to 30 days post-hatching, abnormal embryogenesis, characterized by the presence of edema and body curvature, was observed in the 7.0 mg/L exposure group but not in any other groups including controls. The body curvature was found to be the result of abnormal development of the spine. All abnormal embryos hatched without delay, but died within 1 week after hatching, suggesting that the combination of the sub-lethal endpoints of edema and abnormal development of the spine during embryogenesis may predict lethal effects in early life stage zebrafish exposed to diclofenac sodium. Further investigations to verify these findings are needed. The value of the no observed effect concentrations for the embryogenesis, survival and growth endpoints were 3.5, 1.8 and >3.5 mg/L, respectively.

Does a major natural disaster change human values and job preferences? The present studies examined whether the experience of a natural disaster experience shifts people's values and job preferences toward pro–social directions. In Study 1 (cross–temporal analysis), we analysed job application data in nine cities in Japan over 12 years and found that the popularity of pro–social occupations (e.g. firefighter) increased after the Great Hanshin–Awaji Earthquake in 1995, in particular the area hit hardest by the quake. In Study 2 (a large national survey), we found that Japanese respondents who had experienced a major earthquake are more likely to hold a pro–social job than those who never experienced a major earthquake. Together, the current findings suggest that the experience of a major natural disaster shifts human values from the egocentric to the allocentric direction, which in turn could result in a social structure that values pro–social occupations. Copyright © 2017 European Association of Personality Psychology

One of complications associated with long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) is peptic ulcer. Recently, we found that orally administered phosphatidic acid (PA) ameliorated aspirin-induced stomach lesions in mice. In this study, we identified PA-rich food sources and examined the effects of the food materials on indomethacin-induced stomach ulcer. Among examined, buckwheat (Fagopyrum esculentum) bran contained the highest level of PA (188 mg/100 g). PA was the richest phospholipid (25%) in the lipid fraction of the buckwheat bran. Administration of the lipid extracts of buckwheat bran significantly ameliorated indomethacin-induced stomach lesions in mice. In contrast, wheat (Triticum durum) bran lipids (PA, 4%) and soybean (Glycine max) lipids (PA, 3%) were not associated with ameliorative effects. These results indicated that PA-rich lipids can be used as an effective supplement for prevention of NSAID-induced stomach ulcer.

The effects of endocrine disruptors, including anti-androgenic chemicals, on aquatic environments have received increased attention in recent years. Currently, the method used to screen chemicals for anti-androgenic activity is called the androgenized female stickleback screen, and it was established by the Organization of Economic Cooperation and Development in 2011 using the three-spined stickleback. However, screening chemicals for anti-androgenic activity has yet to be established using Japanese medaka. Thus, the purpose of this study was to establish a screening method for anti-androgenic activity utilizing the number of papillary processes in Japanese medaka (Oryzias latipes) as an indicator of the chemical's anti-androgenic activity. Thus, at 35 days post-fertilization, medaka were exposed to fenitrothion, an anti-androgenic compound, for 28 days. In the control group, the formation of papillary processes was observed in XY medaka, but not in XX medaka. However, after fenitrothion exposure, the number of papillary processes was significantly decreased in a dose-dependent manner in XY medaka; in the 300 μg l-1 concentration group, four of 11 XY medaka showed no papillary processes even if there were no significant effects on total length and wet body weight compared with the control group. Our results indicate that the number of papillary processes in Japanese medaka can be used as an indicator of anti-androgenic activity and that this model may prove useful as a chemical screening method. Copyright © 2016 John Wiley & Sons, Ltd.

The valuable relationships hypothesis posits that people are inclined to reconcile with their valuable-relationship partners. Focusing on a particular type of credible conciliatory signal (i.e., costly apology), the present study tested this hypothesis from the perpetrator's perspective. In studies 1 and 2, after imagining that they had committed an interpersonal transgression against one of their real friends, participants ( N =529 and 311 in studies 1 and 2, respectively) rated their willingness to incur a cost in order to apologize to the victim. Apology cost was operationalized as "canceling plans to make an apology as soon as possible" in study 1, and as "offering compensation" in study 2. The results showed that the instrumentality of the partner to achieving the participants' goals would increase their willingness to make a costly apology, after controlling for the participants' sex, version of the transgression scenario, closeness to the victim, and expected forgiveness of the victim. To ensure the external validity of this finding, studies 3 and 4 asked participants to recall one of their interpersonal transgression experiences, and to report whether they had offered compensation for it ( N =190 and 224 in studies 3 and 4, respectively). Study 3 confirmed the hypothesis, while study 4 did not directly support it. However, study 4 did show that participants were more willing to reconcile with their valuable partners. Taken together, these results indicate that the valuable relationships hypothesis applies not only to victims, but also to their perpetrators as well.

Recent experimental studies have accumulated evidence about self-punishment. In accordance with the evolutionary perspective that shame has a reputation-maintenance function, we speculated that shame would promote self-punishment. Accordingly, we tested whether proneness to shame would predict self-punishment. In the first phase of the experiment, 98 undergraduates completed the Test of Self-Conscious Affect (TOSCA), a standard measure of proneness to shame and guilt. About 2 months later, 50 of the original participants took part in a self-punishment experiment, in which they all unintentionally made an unfair resource allocation, and then had the opportunity to inflict self-punishment by abandoning some of the money they had allocated to themselves. The amount of money the participants relinquished was significantly correlated with their shame-proneness. The intensity of posttransgression shame mediated the effect of shame-proneness on self-punishment. These results provide support for the evolutionary theorization of shame as a reputation-maintenance emotion.

Lysophosphatidic acid (LPA) is a bioactive phospholipid that induces diverse biological responses. Recently, we found that LPA ameliorates NSAIDs-induced gastric ulcer in mice. Here, we quantified LPA in 21 medicinal herbs used for treatment of gastrointestinal (GI) disorders. We found that half of them contained LPA at relatively high levels (40-240 μg/g) compared to soybean seed powder (4.6 μg/g), which we previously identified as an LPA-rich food. The LPA in peony (Paeonia lactiflora) root powder is highly concentrated in the lipid fraction that ameliorates indomethacin-induced gastric ulcer in mice. Synthetic 18:1 LPA, peony root LPA and peony root lipid enhanced prostaglandin E

Curiosity is a fundamental part of human motivation that supports a variety of human intellectual behaviors ranging from early learning in children to scientific discovery. However, there has been little attention paid to the role of curiosity in aging populations. By bringing together broad but sparse neuroscientific and psychological literature on curiosity and related concepts (e.g., novelty seeking in older adults), we propose that curiosity, although it declines with age, plays an important role in maintaining cognitive function, mental health, and physical health in older adults. We identify the dopaminergic reward system and the noradrenergic system as the key brain systems implicated in curiosity processing and discuss how these brain systems contribute to the relationship between curiosity and adaptive aging.

The present study investigated a genetic underpinning of human reconciliation. Recent research has shown that people tend to inflict self-punishment as part of a repertoire of reparative acts. Since empathy generally facilitates reparative acts, we hypothesized that there exists an association between an empathy-related genetic variation, a single nucleotide polymorphism (SNP) in the oxytocin receptor ( OXTR ) gene (rs53576 A vs. G), and the tendency toward self-punishment. Participants played a modified version of the dictator game, in which they made an unfair allocation unintentionally. They then had the opportunity to punish themselves by reducing some portion of their monetary reward. The results showed that the participants with the GA or GG genotype, compared to the participants with the AA genotype, were more likely to engage in self-punishment after making the unfair allocation unintentionally. This effect was not mediated by self-critical feelings (guilt and shame) associated with the unfair allocation. The present study suggests that the OXTR polymorphism is associated with a human reconciliatory tendency.

Human friendship poses an evolutionary puzzle, since people behave more generously toward their friends than the tit-for-tat strategy stipulates. A possible explanation is that people selectively behave in a generous manner toward their true friends, but not toward fair-weather friends. Social psychological studies have suggested that people use a partner's attentiveness toward them as a cue to distinguish these two types of friends. Accordingly, it was hypothesized that people would increase their intimacy with a partner who was attentive to them. This hypothesis was tested by disentangling the frequent confounding between a partner's attention and the benefits provided by the attentive partner in two scenario experiments (studies 1a and 1b) and three laboratory experiments (studies 2a to 2c). In study 1, a partner's attentiveness was manipulated independently of the benefit provided by the partner. In study 2, the partner's attention was experimentally dissociated from any potential benefit. These studies consistently showed that the participants increased their intimacy with a partner when they received attention from the partner. This result implies that models of the evolution of friendship must incorporate information exchange regarding the valuation of the relationship, as well as the exchange of fitness-related costs and benefits.

The effects of endocrine disruptors, including anti-androgenic chemicals, on aquatic environments have received increased attention in recent years. Currently, the method used to screen chemicals for anti-androgenic activity is called the androgenized female stickleback screen, and it was established by the Organization of Economic Cooperation and Development in 2011 using the three-spined stickleback. However, screening chemicals for anti-androgenic activity has yet to be established using Japanese medaka. Thus, the purpose of this study was to establish a screening method for anti-androgenic activity utilizing the number of papillary processes in Japanese medaka (Oryzias latipes) as an indicator of the chemical's anti-androgenic activity. Thus, at 35 days post-fertilization, medaka were exposed to fenitrothion, an anti-androgenic compound, for 28 days. In the control group, the formation of papillary processes was observed in XY medaka, but not in XX medaka. However, after fenitrothion exposure, the number of papillary processes was significantly decreased in a dose-dependent manner in XY medaka; in the 300 μg l