A novel photoplethysmography technique to derive normalized arterial stiffness as a blood pressure independent measure in the finger vascular bed.

Stiffening of the small artery may be the earliest sign of arteriosclerosis. However, there is no adequate method for directly assessing small arterial stiffness. In this study, the finger arterial elasticity index (FEI) was defined as the parameter n which denotes the curvilinearity of an exponential model of pressure (P)-volume (V(a)) relationship (V(a) = a - b exp (-nP)).

Responses of ultra-weak chemiluminescence and secretory IgA in saliva to the induction of angry and depressive moods.

Oxidative damage to tissues and cells contributes to disease processes. We used ultra-weak chemiluminescence (uwCL) as an indicator of oxidative activity to examine the effects of psychological challenges on oxidative responses. We also examined the association of underlying psychological characteristics with oxidative and immune responses.

The effects of depressive symptoms on cardiovascular and catecholamine responses to the induction of depressive mood.

We examined the effects of depressive symptoms on cardiovascular and catecholamine responses to the induction of different mood states. Fifty-five healthy men and women (mean age 23.4 +/- 3 years) were recruited.

Attention-Affect Check List: A self-report measure of acute mental stress.

Given a hint from Lang, Bradley, and Cutbert's (1997) defense cascade, two cognitive processes, instead of passive versus active behavioral coping, which seem to have differential effects on the provocation of vascular- versus cardiac-dominant reaction pattern during mental stress were advocated: attention (Attent) versus unpleasant affect (UnplAff). Based on this notion the Attention-Affect Check List (AACL) was developed as a self-report measure. In addition, items on uncontrollability (Uncontr) were prepared for the purpose of checking whether heightened Attent and UnplAff are accompanied by alterations in Uncontr.

[Application of finger arterial compliance-blood pressure function for an evaluation of the sympathetically mediated vascular tone].

Normalized pulse volume (NPV, Sawada, Tanaka, & Yamakoshi, 2001) was calculated on a beat-to-beat basis by dividing the ac component by the dc component in near-infrared finger photoplethysmogram. Finger arterial compliance index (CI) was obtained by dividing NPV by the respective pulse pressure. Twelve female subjects underwent immersions of the contralateral hand in water at two different temperatures (44 degrees C, 22 degrees C).

Examination of normalized pulse volume-blood volume relationship: toward a more valid estimation of the finger sympathetic tone.

The pulsatile ac component (DeltaI) superimposed on the transmitted dc components (I: tissue plus blood) are obtained from a near-infrared finger photoplethysmogram using a wavelength of 810 nm. Only the dc component is given in an ischaemic circulatory state (I(t): tissue only). Based on Lambert-Beer's law, normalized pulse volume (NPV; =DeltaI/I) and blood volume [BV; =ln(I(t)/I)] have recently been advocated as quantitative measures.

Finger arterial compliance as determined by transmission of light during mental stress and reactive hyperaemia.

A near-infrared finger photoplethysmogram adopting a wavelength of 810 nm provides data pertaining to the pulsatile a.c. component of finger blood flow (delta I) superimposed on the transmitted d.