Nitric oxide (NO) synthesis in endothelial cells is impaired in diabetes. We previously showed that impaired NO synthesis in the spontaneously diabetic BB (BBd) rat is due to decreased levels of tetrahydrobiopterin (BH4), secondary to decreased expression of GTP cyclohydrolase I (GTPCH). The aim of this study was to utilize adenoviral GTPCH gene transfer to reverse BH4 deficiency and repair the ability of endothelial cells to produce NO. GTPCH gene transfer increased BH4 levels in BBd endothelial cells from 0.17 +/- 0.02 (mean +/-SE) to 73.37 +/- 14.42 pmol/million cells and NO production from 0.77 +/- 0.07 to 18.74 +/- 5.52 nmol/24 h/million cells. To demonstrate a functional effect of increasing BH4 concentrations in tissues, we transferred GTPCH into aortic rings from BBd and Zucker diabetic fatty (ZDF) rats, models of human type I and type II diabetes, respectively. GTPCH gene transfer led to a dose-dependent increase in acetylcholine-induced vasorelaxation, preventable by inhibiting NO synthase. Maximal relaxation of virus-treated rings (10(10) virus particles/ml) to acetylcholine was significantly higher than sham-treated rings (BBd 64% vs. 37%, P<0.005; ZDF 80% vs. 44%, P<0.05). This study demonstrates that GTPCH gene transfer can reverse BH4 deficiency in both type I and type II diabetes and provides an experimental basis for using gene therapy to treat cardiovascular complications in diabetic patients.
The aim of this study was to report the outcome of all clinical pregnancies obtained after intracytoplasmic sperm injection (ICSI) performed during a 5 year period at two fertility clinics, with special reference to delivery outcome associated with different sperm origin and quality and the transfer of fresh or frozen-thawed pre-embryos. A total of 1293 clinical pregnancies was analysed. Deliveries occurred in 75.9% (n = 982) and early spontaneous abortion, late spontaneous abortion and ectopic pregnancy in 21.4, 1.0 and 1.2% respectively. Multiple birth occurred in 21.3% (208 sets of twins and one set of triplets) of the deliveries, with the highest incidence in the epididymal sperm group (30.2%) and lowest in the cryopreserved group (13.7%). A total of 1192 infants was born. Preterm birth occurred in 15.7% of all deliveries. Preterm birth was not related to sperm origin or quality but was related to multiple birth. The prematurity rate was 8.4%, 42.3% and 100% for singletons, twins and triplets respectively. Singleton infants born after cryopreservation as embryos had a significantly higher birthweight than the ejaculated sperm group with fresh embryo transfer. The perinatal mortality rate was 11.7 per 1000 born infants. Eighty-seven of the 1192 infants (7.3%) had a malformation, 40 of which were minor. The perinatal mortality rate and the malformation rate were similar in the different subgroups. Prenatal karyotyping was performed on 149 fetuses (12.5%) and abnormal results were found in four cases (2.7%). In conclusion, obstetric outcome of ICSI pregnancies was similar to that of conventional IVF and was not influenced by sperm origin or quality. The high incidence of multiple births is still the major concern.
When using a starting dose of 225 IU rhFSH combined with the multiple dose of 0.25 mg cetrorelix from stimulation day 6, significantly more oocytes were obtained than with a starting dose of 150 IU rhFSH.
Percutaneous epididymal sperm aspiration (PESA) for retrieval of spermatozoa for intracytoplasmic sperm injection (ICSI) is a new simplified technique in the treatment of men with obstructive azoospermia. There has been a fear that the PESA procedure, being blind, could cause damage to the epididymal duct system and make it impossible to retrieve spermatozoa if a repeated procedure is required. We report here on repeated PESA procedures from the same unilateral epididymis. Twenty-seven men with obstructive azoospermia were investigated retrospectively regarding sufficiency of the number of motile spermatozoa for ICSI, fertilization rate (FR) and possibility of collecting spermatozoa for cryopreservation in repeated PESA procedures. Sufficient motile spermatozoa for ICSI were found in a similar proportion of men at the first two attempts: 91 and 89% respectively. Fertilization rate and the possibility of collecting spermatozoa for cryopreservation were also similar at the first two PESA procedures: 62 versus 67% and 33 versus 33% respectively. At the third procedure, motile spermatozoa for ICSI were retrieved in 86% (6/7), FR was 47% and spermatozoa were cryopreserved in one case. Two men underwent a fourth PESA. In both cases, a sufficient number of motile spermatozoa for ICSI was found and FR was 62%. This study shows that in men with obstructive azoospermia, PESA can be repeated on the same unilateral epididymis up to three times, with good opportunity of retrieving sufficient motile spermatozoa for ICSI.
No differences were found in overall pain experienced during the entire oocyte retrieval procedure with POB compared to PCB.
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