Possibility of using salivary ultra-weak chemiluminescence as a biomarker for feelings of anxiety in hospital settings.

The aim of this study was to assess whether a particular value of noninvasive salivary ultra-weak chemiluminescence (UCL) could be used as a biomarker of psychological stress. Our study covered two groups. Group 1 comprised six healthy volunteers who stayed in a hospital for one night and group 2 comprised 15 patients with lung cancer and 24 patients with respiratory diseases other than lung cancer who were in hospital for an extended stay. First, we evaluated the UCL of saliva from six healthy volunteers before and after one night in hospital. Immunoglobulin A (IgA) concentrations were also measured. The integrated intensity value of UCL was correlated with the IgA concentration (correlation coefficient 0.90). Second, in the case of a long hospital stay, we found that the maximum salivary UCL intensities were higher in patients with lung cancer than in those with respiratory diseases other than lung cancer or in 28 healthy controls. Copyright © 2016 John Wiley & Sons, Ltd.

Comparison of peroxidase response to mental arithmetic stress in saliva of smokers and non-smokers.

Saliva is the first body fluid to encounter exogenous materials or gases such as cigarette smoke (CS). The aim of this study was to examine whether smoking affects oral peroxidase (OPO) reactivity to mental stress. The subjects were 39 non-smokers and 10 smokers. In the experiment, the Kraepelin psychodiagnostic test as a psychological stressor and saliva was sampled 30 min before, just before, immediately after, and 30 min after the beginning of the test. OPO reactivity to the test between smokers and non-smokers was measured in addition to uric acid concentration, flow rate, IgA, thiocyanate (SCN-) concentration, amylase activity as a salivary stress marker, and ultra-weak chemiluminescence (UCL) level, which is indicative of salivary antioxidative and antibacterial abilities. Moreover, we studied the effect of smoking on the response of salivary peroxidase (SPO) and myeloperoxidase (MPO) activity to mental stress, respectively. The results showed that the IgA concentration, amylase activity, SCN(- concentration, and UCL level are higher in the non-smoking group than smoking group and the IgA concentration and UCL level increased in the non-smokers significantly just after the Kraepelin test. The levels of SCN-) were higher in smokers than in non-smokers and OPO activity was greater in the non-smoking group in all sessions. Furthermore, only the non-smokers had significantly increased MPO activity just after the test. MPO may play a crucial role in the response to acute psychological stress besides inflammation, and CS suppresses this response significantly.

Development of a saliva collection device for use in the field.

BACKGROUND: For monitoring biomarkers, saliva has several distinct advantages over other biological fluids. Saliva sampling is relatively non-invasive and enables the collection from either adults or infants under many different circumstances. However, there is no collection device that can be speedily used for analysis in the field. The aim of the present study was to evaluate the suitability of a new device, termed Muddler, compared with commercially available collection devices. METHODS: Saliva was collected from healthy volunteers. The collection devices such as Muddler, eye sponge, Salivette® Cotton (SC) and Salivette® Synthetic (SS) were evaluated in terms of the volume and/or composition of the collected saliva. The amounts of immunoglobulin A (IgA) and lactofferin in saliva were assessed by the enzyme-linked immunosorbent assays with the corresponding antibodies. Amylase activity was measured using a commercially available kit, and high molecular weight complexes including mucin were assessed by SDS-PAGE staining. RESULTS: A newly developed Muddler, which was made of plastic plate, was the best device for collecting a constant volume of saliva among all the devices examined in the present study. Furthermore, Muddler can collect without change in composition of salivary proteins such as IgA, lactoferrin, amylase, and mucin complex, whereas the levels of the salivary proteins obtained with all the commercial devices used were clearly different from those in original saliva. CONCLUSIONS: The newly developed Muddler was the best collection device in terms of the accuracy of collection and the reliability of measurements among all the devices examined in the present study.