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1.
Calcium ionophore-induced acrosome reaction correlates with fertilization rates in vitro in patients with teratozoospermic semen 总被引:5,自引:3,他引:5
The aim of this study was to determine the relationship between calcium
ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing
ability. Semen samples remaining after preparation for standard IVF were
studied in 109 patients who had sperm concentrations > or =20 x
10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected
by centrifugation on a Percoll gradient. Semen analysis was performed using
standard methods. Patients with higher (>50%, n = 76) fertilization
rates had significantly higher ionophore-induced AR than patients with
lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P
< 0.05). When the data from all patients were analysed by logistic
regression, only the percentage sperm motility in insemination medium and
ionophore-induced AR were significantly related to fertilization rates.
Similar results were also obtained when the data from a subgroup of
patients with poor (<15% normal) sperm morphology were analysed.
However, when patients with normal sperm morphology > or =15% were
analysed separately, only sperm count and the percentage of spermatozoa
with progressive motility in semen were significantly related to
fertilization rates. In conclusion, ionophore- induced AR was significantly
related to fertilization rates in vitro mainly in patients with
teratozoospermic semen. Tests for ionophore- induced AR may provide
additional information about sperm fertilizing ability but may not indicate
specific defects of the physiological AR.
相似文献
2.
Stein TP; Oram-Smith JC; Leskiw MJ; Wallace HW; Long LC; Leonard JM 《The American journal of physiology》1976,230(5):1321-1325
3.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
4.
Clarke GN; Bourne H; Hill P; Johnston WI; Speirs A; McBain JC; Baker HW 《Human reproduction (Oxford, England)》1997,12(4):722-726
Donor insemination (DI) using cryopreserved semen commenced at The Royal
Women's Hospital in 1976. Over the next 15 years we performed 5953
treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live
births. In-vitro fertilization (IVF) using donor spermatozoa commenced in
1986. Over the next 5 years we performed 303 treatment cycles for 185
couples. Including subsequent transfer of cryopreserved embryos, a total of
33% of couples achieved a successful pregnancy by IVF. Statistical analysis
indicated that, for DI pregnancies, the most important semen variable was
the percentage post-thaw motility, whilst for normal fertilization in IVF
it was the pre-freeze motility. These results may be explained by the
compensatory effects of post-thaw processing of spermatozoa for IVF, but
not for DI in our clinic.
相似文献
5.
de Groot FM de Bart AC Verheijen JH Scheeren HW 《Journal of medicinal chemistry》1999,42(25):5277-5283
New prodrugs of daunorubicin and doxorubicin designed for selective activation by the serine protease plasmin are described. The low toxic prodrugs 3, 4, and 5 are converted to the corresponding cytotoxic drugs upon proteolysis by the tumor-associated protease plasmin. Application of a self-eliminating spacer was essential for enzyme activation. A prodrug containing a chloro-substituted spacer was synthesized with the aim of enhancing the rate of conversion by plasmin. All prodrugs were highly stable in buffer solution and in serum and on the average 15-fold less cytotoxic than the parent drugs in seven human tumor cell lines. A marked in vitro selectivity was demonstrated by incubation of the doxorubicin prodrugs with a plasmin generating MCF-7 breast cancer cell line transfected with urokinase-type plasminogen activator (u-PA) in comparison with the nontransfected nonplasmin generating cell line. Prodrugs 4 and 5 showed the same cytotoxic effect as the free parent drug doxorubicin in the u-PA transfected cells, indicating complete conversion of the prodrug by plasmin. Addition of the plasmin inhibitor Trasylol drastically increased the ID(50) values in the u-PA transfected MCF-7 cells for both prodrugs 4 and 5. 相似文献
6.
Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
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