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51.
Hydrosalpinges adversely affect markers of endometrial receptivity   总被引:22,自引:10,他引:22  
While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.   相似文献   
52.
采用生物素结合的葡聚糖胺顺行示踪法研究了大鼠视皮质主要胼胝体投射区即17/18a交界区胼胝体轴突的生后发育和形态。在生后5天时,此交界区胼胝体轴突从白质向灰质Ⅰ层垂直生长,在灰质内仅有极少量的侧支抽芽。至生后13天时,皮质Ⅰ层最先出现致密的由胼胝体轴突终支组成的终末丛。到生后17天时,类似的终末丛也见于皮质Ⅱ/Ⅲ,Ⅴ和Ⅵ层,这种分布型式与成年大鼠者相似。以上结果表明,绝大部分胼胝体轴突首先生长到达Ⅰ层并先在Ⅰ层发出终支,然后再在其它皮质层发出侧支及终支,因而提示皮质Ⅰ层在胼胝体联系的生后发育中可能发挥重要作用。  相似文献   
53.
54.
Attitudes about genetic risk of couples undergoing in-vitro fertilization   总被引:1,自引:0,他引:1  
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk of having a child with a genetic abnormality. In a sample of 55 consecutive couples starting IVF, only 33% had no genetic risk factor. The most common genetic risks were advanced maternal age and possible abnormalities associated with severe male infertility. Despite education on these risks, 71% of couples had no interest in receiving formal genetic counselling. Only 14% of couples at risk would consider using a gamete donor to avoid transmitting a genetic disorder to a child. The triple test to screen for fetal abnormalities was acceptable to 82% of couples, but only 47% planned to have amniocentesis or chorionic villi sampling. Couples were significantly more likely to opt for prenatal testing if they would consider terminating a pregnancy should the fetus have a severe genetic abnormality (P < 0.01). Roman Catholic couples tended to have more conservative attitudes about pregnancy termination. Socio-economic status and whether the infertility factor was male or female were not predictors of a couple's attitudes.   相似文献   
55.
Embryos produced by in-vitro fertilization (IVF) may produce less platelet-activating factor (PAF) than is optimal for development. It was previously shown that supplementation of culture media with PAF results in a significant increase in pregnancy rate. Human embryos are often cultured in media supplemented with serum containing the enzyme PAF:acetylhydrolase (PAF:AH; EC 3.1.1.47), which hydrolyses PAF to its inactive form, lyso-PAF. Thus, effective supplementation of media with PAF requires inactivation of this enzyme. In this study we examine the efficacy of the methods of PAF:AH deactivation used for PAF supplementation of IVF culture medium. When the effectiveness of a commonly used acid treatment protocol (pH 3.0 at room temperature for 5 min) was examined, it was found that it was not completely effective for the majority of sera. When synthetic PAF was added to 18 serum samples which had been acid treated, five had 90-100% of the original PAF remaining after 24 h (showing that the acid treatment was effective), eight had from 10-90% of the original PAF remaining after 24 h, and five samples had 0-10%. The extent to which PAF:AH was susceptible to deactivation was not associated with the activity in the serum prior to treatment, the serum oestradiol concentration, or the cause of infertility. The period of acidification and the incubation temperature were assessed to develop a new acid-treatment protocol (20 min acid treatment at 37 degrees C) which was able to deactivate PAF:AH effectively in all sera (53/53) examined. A trial was performed to assess the effect of acid treatment of serum for 5 min at room temperature compared with the new protocol (20 min at 37 degrees C) on IVF outcome, following PAF supplementation of IVF culture medium. Oocyte recovery, fertilization and embryo development rates were equivalent for both groups and approximately equal numbers of embryos were transferred or cryopreserved. Pregnancy rates were not significantly different (14.6 versus 20.0%) for the two treatments, with a trend towards a higher pregnancy rate with the new acid- treatment protocol. The results show that this new procedure for acid treatment of serum in combination with PAF supplementation does not have detrimental effects on embryos and their pregnancy outcome and is therefore suitable for use in IVF.   相似文献   
56.
The effect of photodynamic therapy (PDT) treatment on the metabolic state of tumor mitochondria is investigated by imaging of tumor redox status. PDT is performed using the photosensitizer pyropheophorbide-2-deoxyglucosamide (Pyro-2DG), which utilizes the glucose import pathway. It is found that Pyro-2DG-induced PDT resulting in a highly oxidized state of tumor mitochondria. This is determined from the redox ratio changes derived from the intrinsic oxidized flavoprotein (Fp) and reduced pyridine nucleotide (PN) [i.e., reduced nicotinamide adenine dinucleotide (NADH)] fluorescence signals observed using a cryoimager. Thus, the redox ratio is a sensitive indicator for providing reliable and informative measurements of PDT-induced tissue damage. In the PDT treated region of the tumor, highly oxidized flavoprotein and diminishing NADH fluorescence is detected, suggesting that flavoprotein and NADH are oxidized by singlet oxygen produced in the photosensitization process.  相似文献   
57.
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X- linked RP (XLRP), has been mapped previously to a chromosome interval of less than 1000 kbp between the DXS1110 marker and the OTC locus at Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization (YRH)', we have recently identified a small XLRP associated microdeletion in this interval, as well as several putative exons including the 3' end of a gene that was truncated by the deletion. cDNA library screening and sequencing of a cosmid centromeric to the deletion has now enabled us to identify numerous additional exons and to detect several point mutations in patients with XLRP. The predicted gene product shows homology to RCC1, the guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our findings suggest that we have cloned the long-sought RP3 gene, and that it may encode the GEF of a retina-specific GTP-binding protein.   相似文献   
58.
Glycogen storage disease due to phosphorylase kinase deficiency occurs in several variants that differ in mode of inheritance and tissue- specificity. This heterogeneity is suspected to be largely due to mutations affecting different subunits and isoforms of phosphorylase kinase. The gene of the ubiquitously expressed beta subunit, PHKB, was a candidate for involvement in autosomally transmitted phosphorylase kinase deficiency of liver and muscle. To identify such mutations, the complete PHKB coding sequence was amplified by RT-PCR of RNA isolated from blood samples of patients and analyzed by direct sequencing of PCR products. The characterization of mutations was complemented by PCR of genomic DNA. In one female and four male patients, we identified five independent nonsense mutations (Y418ter; R428ter; Y974H+E975ter; Q656ter in two cases), one single-base insertion in codon N421, one splice-site mutation affecting exon 31, and a large deletion involving the loss of exon 8. Although these severe translation-disrupting mutations occur in constitutively expressed sequences of the only known beta subunit gene of phosphorylase kinase, PHKB, they are associated with a surprisingly mild clinical phenotype, affecting virtually only the liver, and relatively high residual enzyme activity of approximately 10%.   相似文献   
59.
A summary is given for the lineage and complementation groupassignments of 153 UV-sensitive mutants of the CHO AA8 cellline. The distribution of mutants among six complementationgroups was highly non-random, with the great majority of theisolates belonging to groups 1 and 2. This asymmetry is consistentwith the known hemizygosity of these two linked loci in CHOcells. The relative numbers of mutants induced in group 2 wasfound to depend greatly on the type of mutagen used. Mutagenesiswith UV radiation, ethyl methanesulfonate (EMS), N-methyl-N'-nitro-N-nitroso-guanidine and 7-bromomethylbenz[a]anthraceneproduced high frequencies of group 2 mutants. In contrast, ICR170and ICR191, which are thought to produce mostly frameshift mutations,yielded very few mutants in group 2. These results are of particularimportance in light of the recent finding that the human ERCC2gene, which corrects group 2 mutants, has very strong homologywith the yeast gene RAD3. RAD3 is an essential gene for viabilityin yeast, and the low recovery of group 2 mutants using theframeshift agents strongly suggests that frameshift mutationstend to be lethal in the hamster ERCC2 locus. Several mutagen-sensitivedouble mutants were isolated in two-step selections from EMS-,mitomycin C- or UV-sensitive parental cells, including the lineUVU1, the first mammalian line with two mutations that affectUV sensitivity. The first mutation inactivated excision repair,and the second mutation appears to have affected some otherrecovery process. UVU1 should be useful for studying recoveryprocesses that are separate from nucleotide excision repair. 1To whom correspondence should be addressed  相似文献   
60.
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