title: Mechanical properties of human autologous tubular connective tissues (human biotubes) obtained from patients undergoing peritoneal dialysis.
abstract: Completely autologous in vivo tissue-engineered connective tissue tubes (Biotubes) have promise as arterial vascular grafts in animal implantation studies. In this clinical study of patients undergoing peritoneal dialysis (PD) (n = 11; age: 39-83 years), we evaluated human Biotubes' (h-Biotubes) mechanical properties to determine whether Biotubes with feasibility as vascular grafts could be formed in human bodies. We extracted PD catheters, embedded for 4-47 months, and obtained tubular connective tissues as h-Biotubes (internal diameter: 5 mm) from around the catheter' silicone tubular parts. h-Biotubes were composed mainly of collagen with smooth luminal surfaces. The average wall thickness was 278 ± 178 μm. No relationship was founded between the tubes' mechanical properties and patients' ages or PD catheter embedding periods statistically. However, the elastic modulus (2459 ± 970 kPa) and tensile strength (623 ± 314 g) of h-Biotubes were more than twice as great as those from animal Biotubes, formed from the same PD catheters by embedding in the beagle subcutaneous pouches for 1 month, or beagle arteries. The burst strength (6338 ± 1106 mmHg) of h-Biotubes was almost the same as that of the beagle thoracic or abdominal aorta. h-Biotubes could be formed in humans over a 4-month embedding period, and they satisfied the mechanical requirements for application as vascular grafts. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1431-1437, 2016.
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan. ny@ncvc.go.jp.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama
authors.affiliation: Department of Kidney and Dialysis, Tenri Hospital, Nara, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kaneko
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Takewa
authors.affiliation: Department of Kidney and Dialysis, Tenri Hospital, Nara, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Okumura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D064592:Autografts; D001705:Bioprosthesis; D057785:Catheters; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D012828:Silicones; D023822:Tissue Engineering
chemical_list: D012828:Silicones
keywords: artificial grafts; biotube; human tissue; in-body tissue architecture; peritoneal dialysis