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To systematically analyze biological changes with spatiotemporal dynamics, it is important to establish a system that is amenable for real-time in vivo imaging at various size levels. Herein, we focused on the developing pupal wing tissues in the pale grass blue butterfly, Zizeeria maha, as a system of choice for a systematic multiscale approach in vivo in real time. We showed that the entire pupal wing could be monitored throughout development using a high-resolution bright-field time-lapse imaging system under the forewing-lift configuration; we recorded detailed dynamics of the dorsal and ventral epithelia that behaved independently for peripheral adjustment. We also monitored changes in the dorsal hindwing at the compartmental level and directly observed evaginating scale buds. We also employed a confocal laser microscopy system with multiple fluorescent dyes for three-dimensional observations at the tissue and cellular levels. We discovered extensive cellular clusters that may be functionally important as a unit of cellular communication and differentiation. We also identified epithelial discal and marginal dents that may function during development. Together, this lycaenid forewing system established a foundation to study the differentiation process of epithelial cells and can be used to study biophysically challenging mechanisms such as the determination of color patterns and scale nanoarchitecture at the multiscale levels.

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Although interleukin-6 (IL-6) has been investigated frequently in stress research, knowledge regarding the biological processes of IL-6 in association with psychosocial stress remains incomplete. This study focused on salivary IL-6 and reports its temporal variation and biological correlates following acute psychosocial stress. Fifty healthy young adults (39 male and 11 female students) were subjected to the psychosocial stress test 'Trier Social Stress Test' (TSST), wherein the participants were asked to deliver a speech and perform a mental arithmetic task in front of 2 audiences. Collection of saliva samples, measurement of heart rate, and assessment of negative moods by visual analogue scales were conducted before, during, and after TSST. Salivary IL-6 levels increased by approximately 50% in response to the TSST and remained elevated for 20 min after the stress tasks were completed. Cluster analyses revealed that individuals with sustained elevation of IL-6 levels following the TSST exhibited a lower cortisol response compared to individuals with lower IL-6 levels. In the correlation analyses, a greater IL-6 response was associated with a higher heart rate during the mental arithmetic task (r=.351, p<.05) and with a lower cortisol response (r=-.302, p<.05). This study demonstrates that salivary IL-6 levels are elevated for a relatively long period following acute psychosocial stress, and suggests that sympathetic activity and cortisol secretion are involved in elevation of salivary IL-6 levels.

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Organisms prefer to receive rewards sooner rather than later because they excessively discount the subjective value of future rewards, a phenomenon called delay discounting. Recent studies have reported an association between cortisol-which is secreted by the hypothalamic-pituitary-adrenal (HPA) axis-and delay discounting. However, no study has examined whether acutely induced psychosocial stress modulates delay discounting. Thus, the present study examined the effect of acute psychosocial stress and its hormonal and inflammatory correlates on the rate of delay discounting. To accomplish this purpose, we assessed the participants' discounting rates using the questionnaire version with inter-temporal choice before and after an acute psychosocial stress task (the Trier Social Stress Test; TSST). The results demonstrated that TSST increased rates of delay discounting in only cortisol responders (not in non-responders), indicating the possible influence of the pathway from the HPA axis to the dopaminergic systems under acute stress. Furthermore, the findings of correlation analysis indicated a U-shaped relationship between baseline level of C-reactive protein and delay discounting rate, suggesting a complex relationship between inflammatory markers and delay discounting rate.

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OBJECTIVE: In this study, we investigated levels and relative ratios of adrenal hormones (including cortisol, dehydroepiandrosterone [DHEA], and DHEA-sulfate [DHEA-S]) and their psychophysiological correlates under acute psychosocial stress in individuals with irritable bowel syndrome (IBS). METHODS: Fifty-three college students participated in the study (male: 42, female: 11; mean age: 22.64years), including 13 individuals with IBS (IBS group) and 40 individuals without IBS (control group). The participants were exposed to a standardized laboratory stressor, which included delivering a speech and performing a mental arithmetic task. We measured subjective stress levels and salivary cortisol, DHEA, and DHEA-S levels at relevant time points before, during, and after the tasks. RESULTS: DHEA-S level and the DHEA-S/DHEA ratio in the IBS group were significantly lower than those in the control group, and the cortisol/DHEA-S ratio in the IBS group was higher than that in the control group throughout the experiment. In the IBS group, the appraisal of a threat was positively correlated with cortisol levels (r=0.61), and the appraisal of controllability was negatively correlated with cortisol levels (r=-0.64) and with the cortisol/DHEA ratio (r=-0.71). The control group showed a significant positive correlation between the appraisal of threat and cortisol levels (r=0.32). CONCLUSION: The present study indicates that individuals with IBS had lower DHEA-S levels, and that their stressful cognitive appraisals under acute psychosocial stress caused the effects of cortisol to dominate. This adrenal hormone response may be involved in exacerbating abdominal symptoms in individuals with IBS.

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The sevenless (sev) cascade plays an inductive role in formation of the R7 photoreceptor, whilst the pokkuri (pok) and tramtrack (ttk) gene products are known to repress R7 induction in developing ommatidia of Drosophila melanogaster. To elucidate how these positive and negative signalling mechanisms co-operate in the normal fate determination of R7, genetic interactions of mutations in the pok locus with ttk and downstream elements of sev including Gap1, raf1, rolled (r1) and seven in absentia (sina) were examined. The eye phenotype of a weak hypomorph, pok 15, was enhanced dominantly by Gap1-mip, a recessive mutation in a gene encoding a down-regulator of Ras1, producing multiple R7 in ommatidia. Ras1 has been reported to activate r1-encoded mitrogen-activated protein (MAP) kinase via Raf1 that is associated physically with Rasl. Ommatidia of raf1 c110 and rl 2/rlEMS64 typically lacked R7 and a few outer photoreceptors. The pok 1 mutation suppressed dominantly the rafl c110 rl2/rlEMS64 eye phenotypes, allowing single R7 cells to develop in ommatidia. The rafl c110 mutation improved adult viability of pok 1 homozygotes. An in vitro experiment demonstrated that MAP kinase phosphorylates Pok protein. Ttk is a transcriptional repressor which binds to the regulatory sequence upstream of the fushi-tarazu (ftz), even skipped (eve) and engrailed (en) coding region. A reduced activity in ttk resulted in enhancement of the pok phenotype. ttk mutations produced extra R7 cells even in sina homozygotes whilst the pok mutation did not. This result indicates that Ttk represses R7 induction downstream of the sites where Pok and Sina function.