Blood flow velocity waveform in the common carotid artery and its analysis in elderly subjects

A contact line pinning based microfluidic platform for modelling physiological flows

This work introduces a contact line pinning based microfluidic platform for the generation of interstitial and intramural flows within a three dimensional (3D) microenvironment for cellular behaviour studies. A contact line pinning method was used to confine a natively derived biomatrix, collagen, in microfluidic channels without walls. By patterning collagen in designated wall-less channels, we demonstrated and validated the intramural flows through a microfluidic channel bounded by a monolayer of endothelial cells (mimic of a vascular vessel), as well as slow interstitial flows within a cell laden collagen matrix using the same microfluidic platform. The contact line pinning method ensured the generation of an engineered endothelial tube with straight walls, and spatially uniform interstitial fluid flows through the cell embedded 3D collagen matrix. Using this device, we demonstrated that the breast tumour cells' (MDA-MB-231 cell line) morphology and motility were modulated by the interstitial flows, and the motility of a sub-population of the cells was enhanced by the presence of the flow. The presented microfluidic platform provides a basic framework for studies of cellular behaviour including cell transmigration, growth, and adhesion under well controlled interstitial and intramural flows, and within a physiologically realistic 3D co-culture setting.

Wireless blood velocity spectra measurement system for healthcare evaluation: reference data

The aim of the present study was to determine the blood velocity and its indices in common carotid artery (CCA) as reference value for clinical and healthcare application using the constructed portable wireless Doppler blood flow velocimeter system. Evaluation of CCA blood velocity waveforms was performed in 202 healthy volunteers in the age range of 20 to 69 years. Multivariate analysis was used to determine the relationship between the fixed factor and the outcome hemodynamic variables after adjustment for the related covariates. Results show a general age-related decrease in flow velocities and change in the velocity waveform. There is also a gender difference in velocity indices, except for peak systolic blood velocity. Gender difference is also found in systolic and pulse blood pressures. The findings suggest that waveform indices provide a more reliable evaluation of effects of aging and gender on CCA flow. In conclusion, normal CCA blood velocity parameters are determined in a total of 202 healthy volunteers between the third and seventh age decade after adjustment for gender and exercise effects. Findings may contribute to improved means of healthcare monitoring and clinical evaluation.

Effects of aging and exercise training on the common carotid blood velocities in healthy men

An age-related alteration in the cardiovascular response to exercise training are evident. The purpose of the study was to investigate the effects of exercise and age on blood velocities in common carotid artery in 82 healthy men between the age ranges of 21 to 67 years old. Blood velocities are characterized to five components of velocity waveforms as peak systolic (S1), second systolic (S2), incisura between systole and diastole (I), peak diastolic (D) and end-diastolic velocity wave (d). Decrease of blood velocities in peak systolic (r= -0.711, P<0.0001) and in peak diastolic velocities (r= -0.521, P<0.0001) with aging are improved and partially restore in particularly older men. The velocity ratio of S2/S2-1 as a reflection index increase with age (r= 0.797, P<0.0001), however is smaller in exercise-trained older compared with sedentary peers. The ratio of 1-I/D as a vascular elastic recoil index decrease with aging (r= -0.640, P<.0001), but is relatively higher in exercise-trained men. Exercise training improves the age-related deterioration in blood velocities and its indices in healthy men. In the further investigations, the assessment of aerobic fitness and vascular aging has potential by using the criteria of peak systolic and peak diastolic, and its indices.

Depression and quality of life in the elderly in a special nursing home

Using a Japanese version of the Self-Rating Depression Scale by Zung (SDS) and the Quality of Life (QOL) rating scale designed by Iida et al. (QOL scale), we compared the QOL and depressive state of special nursing home residents and the elderly in the general community. The QOL scale has four categories: physical functioning, emotional adjustment, interpersonal relationships and attitudes toward life. High scores in either examination indicate a greater impairment. The SDS scores of the residents in the special nursing home were significantly lower than those of the elderly in the community, but the scores in 3 categories and the total score, except for those of physical functioning of the QOL, were significantly higher in the nursing home residents. In the nondepressed elderly rated by the SDS, the physical functioning score of the elderly in the community significantly exceeded that of the special nursing home residents. In the depressed elderly, all the scores including the total score were significantly higher than those in the special nursing home residents. Our results suggest that while the QOL of the depressed elderly in a special nursing home was poorer than that of the elderly in the community, their depression could be treated. However, the QOL cannot be improved by treatment alone.