ABSTRACT. We examined the influence of the cytochrome P450 3A5 (CYP3A5) genes in both donors and recipients on the concentrationdosage ratio (C/D) of tacrolimus in Chinese liver transplant patients. Fifty-one adult liver transplant patients who received tacrolimus were included in this study. The CYP3A5 polymorphism in donors and recipients was determined at the time of transplantation, and tacrolimusbased immunosuppressive therapy was started based on each patient's genetic constitution. The relationship between the C/D of tacrolimus for 3 months after surgery and the CYP3A5 genotype was analyzed. A stepwise regression model was used to analyze the relationship between C/D of tacrolimus and genotype, time course, age, and liver weight in liver transplant patients. Three months after liver transplantation, C/D was both affected by the CYP3A5 genotype of both the donors and (2015) the recipients. The C/D of tacrolimus in patients with the CYP3A5*1 allele or carrying CYP3A5*1 allele in the liver was lower than that in CYP3A5*3/*3 patients with the CYP3A5*3/*3 genotype in the liver (P < 0.01). The CYP3A5*1 genotype in donors as well as in patients both contributes to interindividual variation in the C/D of tacrolimus in adult liver transplantation.

Objective The rapid innovation of the endovascular armamentarium results in a decreased number of indications for a classic surgical approach. However, a middle cerebral artery (MCA) aneurysm remains the best example of one for which results have favored microsurgery over endovascular intervention. In this study, the authors aimed to evaluate the experience and efficacy regarding surgical outcomes after applying internal maxillary artery (IMA) bypass for complex MCA aneurysms (CMCAAs). Methods All IMA bypasses performed between January 2010 and July 2018 in a single-center, single-surgeon practice were screened. Results In total, 12 patients (9 males, 3 females) with CMCAAs managed by high-flow IMA bypass were identified. The mean size of CMCAAs was 23.7 mm (range 10-37 mm), and the patients had a mean age of 31.7 years (range 14-56 years). The aneurysms were proximally occluded in 8 cases, completely trapped in 3 cases, and completely resected in 1 case. The radial artery was used as the graft vessel in all cases. At discharge, the graft patency rate was 83.3% (n=10), and all aneurysms were completely eliminated (83.3%, n=10) or greatly diminished (16.7%, n=2) from the circulation. Postoperative ischemia was detected in 2 patients as a result of graft occlusion, and 1 patient presenting with subarachnoid hemorrhage achieved improved modified Rankin Scale scores compared to the preoperative status but retained some neurological deficits. Therefore, neurological assessment at discharge showed that 9 of the 12 patients experienced unremarkable outcomes. The mean interval time from bypass to angiographic and clinical follow-up was 28.7 months (range 2-74 months) and 53.1 months (range 19-82 months), respectively. Although 2 grafts remained occluded, all aneurysms were isolated from the circulation, and no patient had an unfavorable outcome. Conclusions The satisfactory result in the present study demonstrated that IMA bypass is a promising method for the treatment of CMCAAs and should be maintained in the neurosurgical armamentarium. However, cases with intra-operative radical resection or inappropriate bypass recipient selection such as aneurysmal wall should be meticulously chosen with respect to the subtype of MCA aneurysm.