Heterotopic Implantation of Decellularized Pulmonary Artery Homografts In A Rodent Model: Technique Description and Preliminary Report

Purpose: Despite a substantial amount of literature on tissue-guided regeneration, decellularization process, repopulation time points and stem cell turnover, more in-depth study on the argument is required. Currently, there are plenty of reports involving large animals, as well as clinical studies facing cardiac repair with decellularized homografts, but no exhaustive rodent models are described. The purpose of this study was to develop such a model in rats; preliminary results are also herein reported. Material and Methods: Fresh or decellularized pulmonary homografts from wild type rats were implanted in the abdominal aorta of green fluorescent protein positive rats. Three experimental groups were build up: sham, fresh homograft recipients and decellularized homograft recipients. The homograft decellularization process was performed with three cycles of detergent-enzymatic treatment protocol. Surgical technique of pulmonary homograft implantation and postoperative ultrasonographic evaluation were also reported; gross, histology and immunohistochemistry analysis on unimplanted and postoperative homografts were also carried out. Results: The median total recipient operating time was 148 minutes, with a surgical success rate of 82%. The decellularization protocol resulted effective and showed a complete decellularization with intact extracellular matrix. At 15 days from surgery, the implanted decellularized pulmonary homografts exhibited cell repopulation in the outer media wall and partial endothelial lining in absence of rejection. Conclusions: Our technique is a feasible and reproducible model that can be fundamental for building a valid study for further exploitation on the field. Even in a short-term follow up, the decellularized pulmonary homografts showed autologous repopulation in absence of rejection.     

Comparison of Sonography and Magnetic Resonance Imaging for Spring Ligament Abnormalities

Objective. The purpose of this study was to determine whether sonography is as accurate as magnetic resonance (MR) imaging for depicting abnormalities of the spring ligament in patients with symptomatic posterior tibial tendon (PTT) dysfunction. Methods. Sixteen patients (18 ligaments) with symptomatic PTT dysfunction were prospectively evaluated with sonography and MR imaging. Results. Magnetic resonance imaging showed spring ligament tears in 8 of 18 feet, including 6 incomplete tears and 2 complete tears. Sonography showed spring ligament tears in 7 of 18 feet, including 6 incomplete tears and 1 complete tear. The findings of sonography and MR imaging were concordant in 17 of 18 feet (94%). Six of the 8 spring ligament tears on MR imaging were associated with posterior tibial tendinosis or tears. Conclusions. Sonography is an effective imaging option in assessing spring ligament abnormalities in patients with symptomatic PTT dysfunction.     

Three-dimensional sonographic findings of a cervical pregnancy.

A cervical pregnancy is an uncommon ectopic pregnancy that accounts for less than 1% of such gestations. This condition is associated with an extremely high risk of massive hemorrhage and previously often required hysterectomy. The current diagnostic modality of this potentially life-threatening condition is transvaginal sonography, supported at times by magnetic resonance imaging. The definitive diagnostic imaging feature of a cervical pregnancy is the location of a gestational sac in the cervix in the presence of a closed internal uterine cervical os. We report the 3-dimensional transvaginal sonographic findings of a cervical pregnancy at 6 weeks' gestation.     

Tetrahydrobiopterin responsiveness in patients with phenylketonuria

OBJECTIVES: To investigate the BH4 response in a group of patients with phenylketonuria (PKU) in order to offer this alternative treatment to the responsive patients. DESIGN AND METHODS: The 24-h-long Phe/BH4 loading test was performed on 64 PKU patients requiring dietary treatment. RESULTS: All patients with mild-PKU and 75% of patients with moderate-PKU were BH4 responsive, while only 11% of classic-PKU patients showed good/partial response (P < 0.0001). The percentages of Phe decrease after the BH4 loading test were significantly different in the three PKU phenotypes (mild PKU: 67.9 +/- 18.7; moderate PKU: 37.4 +/- 16.8; and classical PKU: 21.9 +/- 13.7; ANOVA with Bonferroni correction: P < 0.0001). We report four mutations (P147S, D222G, P275S, and P362T) not previously associated with BH4 responsiveness, all of them combined with mutations with zero predicted residual activity. CONCLUSION: Both the percentage of Phe decrease and the Phe value achieved 24 h after BH4 loading are valuable data in predicting a response. We report four mutations not previously associated with BH4 responsiveness.