Stress-related Substances Research Articles

妊娠中の労働による健康影響と心理的ストレス

Modern society demands working conditions in which pregnant women can successfully deliver children and maintain a professional position. The aim of this study is to investigate the effects of work on the health and psychological stress in working women and their newborns. We reviewed twenty-eight publications and found that health problems in working women occur at high rates. However, there is no report investigating the mechanism by which health problems occur, or describing the precise working conditions and symptoms in pregnant women who are engaged in work outside the home. In addition, the literature uses subjective evaluations, including psychological tests, to quantify stress and anxiety, but no biochemical analyses of stress-related substances were conducted. We suggest that a standard index to represent working conditions and job category, as well as an investigation of the workload of house-keeping, is needed to understand the total work effort by pregnant women in modern times. Finally, measurement of stress-related biological markers may be effective in the investigation from various perspectives of occupational stress in pregnant women.

The molecular basis for stress-induced acquisition of somatic embryogenesis

Somatic embryogenesis (SE) has been studied as a model system for understanding of molecular events in the physiology, biochemistry, and biology areas occurring during plant embryo development. Stresses are also the factors that have been increasingly recognized as having important role in the induction of SE. Plant growth regulators such as 2,4-dichlorophenoxyacetic acid (2,4-D), ABA, ethylene, and high concentrations of 2,4-D are known as stress-related substances for acquisition of embryogenic competence by plant cells. Gene expression analysis in both the proteome and transcriptome levels have led to the identification and characterization of some stress-related genes and proteins associated with SE. This review focuses on the molecular basis for stress-induced acquisition of SE.

Association Between Stress-Related Substances in Saliva and Immune Substances in Breast Milk in Puerperae

We examined the association between biochemical parameters of stress in puerperae and immune substances in breast milk. The participants were 22 mothers 2 weeks after delivery, with normal pregnancy/delivery and a normal puerperal course. We measured the levels of secretory immunoglobulin A (SIgA) and cortisol in saliva and the level of SIgA and the leukocyte count in breast milk and investigated their association. There was a positive correlation between the salivary and breast milk levels of SIgA (r = .536, p < .05). However, there were no correlations among the salivary level of cortisol and the level of SIgA and leukocyte count in breast milk. The only association found in our study was between the salivary and breast milk SIgA. The lack of association among SIgA and cortisol may be related to a variety of factors such as production site, diurnal rhythms, and the interval between stress stimulation in mothers and the response of the biomarker.

Development of an On-site Measurement System for Salivary Stress-related Substances Based on Microchip Capillary Electrophoresis Technology

Psychological stress is of major importance to all age groups in recent years, and may lead to mental disorder and various diseases. An objective and quantitative method for measuring salivary stress-related substances is highly desired because saliva collection is easy, stress free and noninvasive. We have developed a rapid and easy-to-use analytical tool for the measurement of cortisol and secretory immunoglobulin A (sIgA) based on microchip technology, immunoselectivity and electrophoretic separation technique. Performing immunoreaction and capillary electrophoresis (CE) separation on microchips is a promising technique for on-site determination of biogenic substances, and has a few advantages over conventional immunoassay methods: reduced sample size, shortening analysis times, high separation efficiency, reduced cost, and downsizing of analytical system. At this stage of our research, some preliminary prototypes of a high-sensitive microchip CE instrument were constructed to determine the stress-related substances in real saliva samples. However, there is not enough detection sensitivity for cortisol analysis. On the other hand, sIgA was successfully analyzed using a laboratory-built microchip CE system and optimal analytical conditions. The sIgA determination is rapid compared with a conventional immunoassay method, and provides an acceptable degree of repeatability and recovery. In the future, microchip technologies will enable total automation and integration of sample preparation. This research has widespread future potential for monitoring multiple stress-related markers within minutes from a trace of saliva, and can contribute to disease prevention and overall good health.