**Acknowledgement**

168 Viscoelasticity – From Theory to Biological Applications

Aorta Aortic aneurysm

Abdomen Hernia

**Table 1.** Proposed Tarumi diseases.

**9. Conclusion** 

**Author details** 

Tetsuya Nemoto and Ryo Kubota

Yusuke Murasawa and Zenzo Isogai

Pelvis Pelvis organ prolapse Vein Varicose vein

Skin Wrinkles, Pressure ulcer

Esophagus Esophageal hiatal hernia

tissue aging in geriatrics.

Common pathogenesis among each Tarumi disease is currently unclear. Smoking is considered to be a precipitating factor in the common pathogenesis of aortic aneurysm and chronic obstructive pulmonary disease (COPD) (29, 30). However, other factors should be investigated for the Tarumi diseases. Tarumi disease may provide a novel perspective of

Therefore, studying Tarumi disease may be a useful step toward understanding common pathogenesis among these diseases. Future directions in Tarumi disease research require pathological, biochemical, and physical studies. Methods presented in this chapter may evaluate the looseness of tissues. Furthermore, surgical intervention using a tissue filler may be a useful method to improve these diseases. Finally, the phenotypical relationship between MFS and Tarumi disease may lead to understanding their common pathogenesis.

Viscoelastic properties of the skin can be measured by various methods and are dependent on the connective tissue architecture formed by ECM molecules. In order to measure the actual viscoelasticity of the skin, we have developed a novel device that can monitor the external forces on the skin in real time. The device can be used for treatment and prevention of pressure ulcers that are affected by viscoelasticity and external force. Among the ECM molecules, versican—a chondroitin sulfate proteoglycan—is an important ECM molecule for viscoelasticity because it constitutes the fibrillin-versican-hyaluronan network. In human pathogenic conditions such as solar elastosis, loss of viscoelastic properties of the dermis is found to occur because of the loss of hyaluronan-binding versican. Marfan syndrome—a genetic connective tissue disease—is also characterized by loss of viscoelasticity in elastic tissues, such as those in the aorta. Finally, aging-associated loss of viscoelasticity and stiffness

of connective tissue are proposed to be the common pathogenesis of Tarumi disease.

*Department of Gerontechnology, National Center for Geriatrics and Gerontology, Japan* 

*Department of Advanced Medicine, National Center for Geriatrics and Gerontology, Japan* 

**Organ Proposed diseases**

Lung Chronic obstructive pulmonary disease

Funding for this study was provided by The Research Funding for Longevity Sciences (21- 18) from the National Center for Geriatrics and Gerontology (NCGG), Japan. We thank Hiroyuki Matsuura and Katsunori Furuta for their cooperation in this study. The authors declare that they have no conflicts of interest.
