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11.
Fertilization, pregnancy and embryo implantation rates after ICSI with fresh or frozen-thawed testicular spermatozoa 总被引:2,自引:1,他引:2
De Croo I; Van der Elst J; Everaert K; De Sutter P; Dhont M 《Human reproduction (Oxford, England)》1998,13(7):1893-1897
This study aimed to determine whether fertilization and implantation rates
after intracytoplasmic sperm injection (ICSI) with fresh or frozen-thawed
testicular spermatozoa were comparable. Between 1 January 1996 and 31
December 1996, 65 ICSI cycles with testicular spermatozoa and 35 cycles
with frozen-thawed testicular spermatozoa were carried out. In 50 out of 65
ICSI cycles, testicular spermatozoa could be retrieved and in 34 out of 35
cycles carried out with frozen-thawed testicular spermatozoa, motile
spermatozoa could be recovered. The fertilization rate after ICSI with
frozen-thawed testicular spermatozoa was significantly lower (71.1%; P <
or = 0.008) than with fresh testicular spermatozoa (79.3%). The pregnancy
rate was similar for both groups (38.2 and 26.5 %). The implantation rate
per transferred embryo, however, was significantly lower in the
frozen-thawed rather than in the fresh testicular sperm group (9.1 versus
24.6%; P = 0.001). The live birth rate per transferred embryo was also
higher in the group in which fresh testicular spermatozoa were used (18.8
versus 7.9% P = 0.043). This retrospective study shows that is possible to
achieve a high fertilization rate after ICSI with both fresh and
frozen-thawed testicular spermatozoa but implantation and live birth rates
per transferred embryo, however, are significantly lower after ICSI with
frozen-thawed than with fresh testicular spermatozoa.
相似文献
12.
13.
Paul De Sutter Dmitri Dozortsev Philippe Vrijens Rita Desmet Marc Dhont 《Journal of assisted reproduction and genetics》1994,11(8):382-388
Purpose
Treatment of aged human oocytes by puromycin allows a high rate of parthenogenetic activation and development until the first cleavage division. This technique was used for the study of the chromosome complement of oocytes which remained unfertilized after in vitro fertilization. Three hundred four unfertilized oocytes were treated with 10 Μg/ml puromycin for 6–8 hr and further cultured for 12–15 hr.Results
Activation occurred in 90.5% of the oocytes. Heterozygous diploids with two pronuclei predominated (61%), which is in contrast to the mouse, where the majority of oocytes activated by puromycin are uniform haploids (89%).Conclusions
Therefore we conclude that puromycin treatment induces retention of the second polar body in human oocytes, unlike in mouse oocytes treated in the same way. Chromosome analysis performed on 182 oocytes suggested a nondisjunction (ND) rate for the second meiotic division of 12.7%. This is a low figure considering the fact that puromycin itself has been reported to induce nondisjunction. For the first meiotic division a ND rate of only 5.6% was found. This rate is lower than the one found in metaphase II arrested oocytes and we believe that this difference is due to the technical differences between the study of meiotic and that of mitotic chromosomes. 相似文献14.
A Collings J Pitk?nen M Strengell M T?htinen A Lagerstedt K Hakkarainen V Ovod G Sutter M Ustav E Ustav A M?nnik A Ranki P Peterson K Krohn 《Vaccine》1999,18(5-6):460-467
OBJECTIVE: HIV accessory protein Nef is expressed early in the infectious cycle of the virus and has been shown to be an effective immunogen in humoral and cellular immune responses. We have used two different self-replicating pBN vectors and one non-replicating pCGal2 derived (pCG) vector expressing HIV-1 Nef in DNA immunisation of mice in order to determine their efficiency in raising humoral and cellular immune responses. DESIGN AND METHODS: The expression of Nef by the three plasmids was tested by transfections into COS-1 cells. Balb/c mice were immunised with the pBN-NEF and pCGE2-NEF constructs using gold particle bombardment. Immunoblotting and immunocytochemistry were used to detect in vitro expression of Nef. 51Cr release assay, ELISA and immunoblotting were used to detect cellular and humoral immune responses in immunised mice. RESULTS: Efficient in vitro expression of Nef was detected in pBN and pCGE2-NEF transfected cells, in pBN-NEF transfected cells the expression lasting up to three weeks. Anti-Nef antibodies in sera of 13 of 16 pBN-NEF immunised mice were detected within four weeks after the last immunisation, whereas only 2 of 12 pCGE2-NEF immunised mice had very weak anti-Nef antibodies. Twelve of the pBN-NEF immunised mice (75%) and 6 the pCGE2-NEF immunised mice (50%) showed Nef-specific cytotoxic T lymphocyte (CTL) responses within four weeks. CONCLUSIONS: We conclude that the three eukaryotic expression vectors tested are capable of inducing a cell mediated immune response towards HIV-1 Nef and should be considered as part of a genetic HIV vaccine. 相似文献
15.
Surgical treatment for cholelithiasis. 总被引:2,自引:0,他引:2
In a retrospective study, the results of 1,631 consecutive operations for cholelithiasis were analyzed. With an overall mortality rate of 0.18 percent and a reoperation rate of 1.3 percent, conventional cholecystectomy proved to be a safe method. Mortality proved to be age dependent, with a zero mortality rate for patients less than 60 years of age. Choledochotomy had a 13-fold greater mortality rate than simple cholecystectomy (0.92 versus 0.07 percent). For acute cholecystitis, we observed an unusual zero mortality rate, whereas the mortality rate in chronic cholecystitis was 0.2 percent. All three patients who died had an accompanying cirrhosis of the liver. Morbidity, defined as reoperation during the same period of hospitalization, was mainly the result of retained stones after choledochotomy; endoscopic papillotomy was the treatment of choice. Cholecystectomy remains the "gold standard" in the treatment of cholelithiasis. 相似文献
16.
Absence of the vagina occurs most frequently in the Rokitansky-Küster-Mayer (RKM) syndrome. Since Küster has reviewed the literature in 1910 many techniques have been described to create a neovagina. We describe a technique in which both a part of the labia minora and of the perineal skin are used as flaps to cover the neovagina and report on the long-term outcome in a series of 16 patients with RKM syndrome treated with this technique. No intra-operative or immediate postoperative complications were recorded. The average depth of the neovagina was 8 cm, at the end of the operation and 1 year later. After 3 months the neovagina was completely lined with vaginal epithelium. In six out of 16 patients scar formation and polypoid formation was observed at the apex of the neovagina. This could be successfully handled by excision and coagulation in all six cases. Ten patients reported a satisfactory sexual life. The technique is simple and easy to perform. The anatomical result and sexual gratification was outstanding in two-thirds of the patients. We conclude that flaps derived from the genital region offer the most physiological tissue for construction of a neovagina. 相似文献
17.
M. Dhont F. De Neubourg J. Van der Elst P. De Sutter 《Journal of assisted reproduction and genetics》1997,14(10):575-580
Purpose:
A matched case–control study of all pregnancies obtained after either IVF or ICSI was conducted to investigate the perinatal outcome.
Methods:
Three hundred eleven singleton and 115 twin pregnancies obtained after assisted reproduction were studied. Controls were selected from a regional register and were matched for maternal age, parity, singleton or twin pregnancy, and date of delivery.
Results:
No significant difference was observed for gestational age at delivery, birth weight, incidence of congenital anomalies, and incidence of perinatal mortality between ART (singleton and twin) pregnancies and spontaneous controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies (52 vs 42%; P < 0.05) and needed more neonatal intensive care (47 vs 26%; P < 0.05).
Conclusions:
From this case–control study it is concluded that the perinatal outcome of ART singleton pregnancies is not different from that in matched controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies and needed more neonatal intensive care. 相似文献
18.
Preconditioning with short cycles improves ischemic tolerance in rat fast- and slow-twitch skeletal muscle 总被引:1,自引:0,他引:1
Mattei A Sutter PM Marx A Stierli P Heberer M Gürke L 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》2000,32(5):297-304
AIM: The aim of this study was to investigate whether the efficacy of ischemic preconditioning (IP) in rat skeletal muscle depends on the duration of the preconditioning cycles. METHODS: Rats were divided into four groups (n = 10 each). The right hindlimb of rats in group A were subjected to 2.5 h of tourniquet ischemia followed by 2 h of reperfusion (I-R). Thereafter, muscular function was analyzed in vitro and high-energy phosphates (HEP) were determined by HPLC. Before I-R, right hindlimbs of rats in groups B-D subjected to IP with three cycles each consisting of 2.5, 5 or 10 min of ischemia followed by reperfusion for the same duration. RESULTS: Postischemic function of the extensor muscle was significantly improved with all three preconditioning protocols. Postischemic function of the soleus muscle was only improved by IP with three cycles of 5 min of ischemia and 5 min of reperfusion. Postischemic HEP tissue levels were not influenced by IP. CONCLUSION: This study shows for the first time that IP increases ischemic tolerance not only of fast-twitch but also of slow-twitch skeletal muscle. The efficacy of IP seems to be less dependent on the duration of the single preconditioning cycle than on the number of cycles performed. Three cycles each of 2.5, 5 or 10 min ischemia and reperfusion significantly improved postischemic skeletal muscle function. Tissue levels of HEPs, however, were not influenced by IP indicating that preservation of HEPs does not play a major role in the effects of IP on rodent skeletal muscle. 相似文献
19.
S. Weyers G. Selvaggi S. Monstrey M. Dhont R. Van den Broecke P. De Sutter G. De Cuypere G. T‘ Sjoen P. Hoebeke 《Gynecological surgery》2006,3(3):190-194
The objective was to compare the outcome of a combined total hysterectomy-vaginectomy-phalloplasty procedure vs. a vaginectomy-phalloplasty procedure in female-to-male (FTM) gender dysphoric individuals, and to report on a large series of vaginectomies in young women. This was a retrospective study and the setting was the Gender Team at Ghent University Hospital. One hundred and five consecutive cases of vaginectomy-phalloplasty with (one-stage) or without (two-stage) total hysterectomy between 1993 and 2003 were included in the study. Patient files of 69 one-stage and of 36 two-stage procedures were reviewed and analysed. Operation time, the need for transfusions, complications, repeated surgery and hospitalisation time were the main outcome measures. Patients were equally distributed over the study period of 10 years. Comparing the two groups, there was a greater need for transfusion in the group of patients undergoing the one-stage procedure. There was no difference in operation time, rate of major complications or hospitalisation time. One-stage sex reassignment surgery (SRS) in FTM transsexual individuals is associated with more blood loss. However, there is no difference in operative and postoperative complications. Vaginectomy seems to be a safe and relatively simple procedure in FTM transsexual patients. 相似文献
20.