Development and Characterization of a Porcine Mitral Valve Scaffold for Tissue Engineering.

Decellularized scaffolds represent a promising alternative for mitral valve (MV) replacement. This work developed and characterized a protocol for the decellularization of whole MVs. Porcine MVs were decellularized with 0.5% (w/v) SDS and 0.5% (w/v) SD and sterilized with 0.1% (v/v) PAA. Decellularized samples were seeded with human foreskin fibroblasts and human adipose-derived stem cells to investigate cellular repopulation and infiltration, and with human colony-forming endothelial cells to investigate collagen IV formation. Histology revealed an acellular scaffold with a generally conserved histoarchitecture, but collagen IV loss. Following decellularization, no significant changes were observed in the hydroxyproline content, but there was a significant reduction in the glycosaminoglycan content. SEM/TEM analysis confirmed cellular removal and loss of some extracellular matrix components. Collagen and elastin were generally preserved. The endothelial cells produced newly formed collagen IV on the non-cytotoxic scaffold. The protocol produced acellular scaffolds with generally preserved histoarchitecture, biochemistry, and biomechanics.

Investigation of the biomechanical integrity of decellularized rat abdominal aorta.

OBJECTIVES: The loss or damage of an organ or tissue is one of the most common and devastating problems in healthcare today. Tissue engineering applies the principles of engineering and biology toward the development of functional biological replacements that are able to maintain, improve, or restore the function of pathological tissues. The aim of the overall project is to study an already existing method for the decellularization of homograft vascular grafts for use in vascular surgery. MATERIALS AND METHODS: The biomechanical integrity of native and decellularized rat aortas was assessed under uniaxial tension tests. For this purpose, 36 male rats (12 Wistar and 24 Dark Agouti [DA]) were used to excise their abdominal aortas. Twelve of the aortas were tested fresh (Wistar and DA rats), within 24 hours from euthanasia, and the rest were decellularized using a modified protocol (DA rats only). Fresh and decellularized samples (n = 12) were subjected to uniaxial tensile loading to failure, and the recorded stress-strain behaviour of each specimen was assessed in terms of 6 biomechanical parameters. RESULTS: No statistically significant differences were found in any of the biomechanical parameters studied between the decellularized DA rat aorta group and both the native DA and Wistar rat aorta groups (P > .05). Also, no significant difference was shown between the native DA and native Wistar rat aorta groups. CONCLUSIONS: The results from this study have shown that the decellularization protocol did not affect the mechanical properties of the native rat aorta. In addition to this, both native Wistar and native/decellularized DA rat aorta groups shared similar mechanical properties.

Vulvodynia and HIV: causal or casual association?

BACKGROUND: No study exists on HIV and vulvodynia. OBJECTIVE: To evaluate vulvodynia in HIV infected women and its possible association with HIV. DESIGN: Cross sectional study. SETTING: Department of Medical and Surgical Sciences, Section of Infectious Diseases, University of Turin. METHODS: 235 HIV positive and 272 HIV negative women were studied for vulvar pain between June 1995 and January 1997. Diagnosis of vulvodynia was based on clinical history, dermatological and vulvovaginal examination, and bacteriology. Colposcopy and vulvar biopsy were performed and psychometric examination was done. RESULTS: Vulvodynia was diagnosed in five women with HIV and in one uninfected woman (odds ratio = 2.5; 95% confidence interval: 0.1-62.6). High neuroticism scores were observed in women with history of vulvar pain, the highest in HIV infected vulvodynia patients (p = 0.000). CONCLUSIONS: Confirming the association of gynaecological pain with neurotic personality, our study suggests causal link between HIV and vulvodynia.