Evaluation of a porcine internal mammary artery (No-React II) as a small-diameter conduit

Background. The patency of biologic small-diameter vascular grafts in the aortocoronary position is still unsatisfactory. Most of the studies suggest that xeno-grafts are to be avoided as an aortocoronary bypass. Methods. The porcine internal mammary artery treated by the No-React II procedure was developed for use as an alternative coronary artery bypass conduit. The attempt of this study was to evaluate the patency and histologic changes of the porcine internal mammary artery in animals. Five calves underwent coronary artery bypass grafting with a porcine internal mammary artery graft to the right coronary artery. After euthanasia of the animals 103 days later, the samples of these grafts were studied morphologically for patency, structural changes, calcifications, acid inflammatory and immunologic response. Results. One animal died during the procedure as result of acute thrombosis of the porcine internal mammary artery graft. In the other 4 animals all grafts became occluded. In the histologic sections of the grafts we noted multiple calcifications and a host-graft immunologic reaction (severe chronic rejection). Conclusions. The present study demonstrates a very poor experience with the porcine internal mammary artery (No-React II) conduit. We do not recommend this prosthesis for clinical use in humans. (C) 1998 by The Society of Thoracic Surgeons

Outcomes of oocyte vitrification in trans masculine individuals

Research question: What are the outcomes and experiences of oocyte vitrification treatment in trans masculine individuals (TMI) before and after testosterone use? Design: This retrospective cohort study was conducted at the Amsterdam UMC in the Netherlands between January 2017 and June 2021. The TMI who had completed an oocyte vitrification treatment were consecutively approached for participation. Informed consent was provided by 24 individuals. Participants (n = 7) who initiated testosterone therapy were advised to stop 3 months before stimulation. Demographic characteristics and oocyte vitrification treatment data were retrieved from medical records. Evaluation of the treatment was collected via an online questionnaire. Results: The median age of participants was 22.3 years (interquartile range 21.1–26.0) and mean body mass index was 23.0 kg/m2 (SD 3.2). After ovarian hyperstimulation, a mean of 20 oocytes (SD 7) were retrieved and a mean of 17 oocytes (SD 6) could be vitrified. Aside from a lower cumulative FSH dose, there were no significant differences between the prior testosterone users and testosterone naïve TMI. The overall satisfaction of oocyte vitrification treatment in participants was high. Hormone injections were considered the most strenuous part of treatment by 29% of participants, closely followed by oocyte retrieval (25%). Conclusions: No difference in response to ovarian stimulation was found for oocyte vitrification treatment between the prior testosterone users and testosterone naïve TMI. The questionnaire identified hormone injections as the most burdensome aspect of oocyte vitrification treatment. This information can be used to improve gender sensitive fertility counselling and fertility treatment strategies