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11.
Mahadevan MM; McIntosh Q; Miller MM; Breckinridge SM; Maris M; Moutos DM 《Human reproduction (Oxford, England)》1998,13(4):979-982
Cryopreservation of human zygotes and embryos has been routinely performed
by in-vitro fertilization clinics for many years. Karran and Legge (1996)
first reported that formaldehyde (FA) present in the cryoprotective
solutions can have a deleterious effect on mouse oocytes. FA is a
cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse
zygotes was investigated. In addition, the concentrations of FA in
propanediol (PROH) obtained from various sources were determined. Pooled
1-cell embryos were dispensed into droplets of modified Ham's F10 or human
tubal fluid containing various concentrations of FA. Since bovine serum
albumin (BSA) may minimize toxicity additional trials were done as above in
the absence of BSA. FA concentration in the standard 1.5 M PROH, from
different sources in water, was measured in the same assay using a standard
curve of 0-100 microM FA. FA in a complex medium had a significant
deleterious effect on embryo development and hatching but only at 1 mM
concentration (P < 0.000001; see Tables I-III). There was no significant
effect of FA at 100 microM. However, in a simple medium even 50 microM FA
decreased embryo hatching. FA was present in 1.5 M PROH from different
sources (range 1.0-35.3 microM concentration). It appears that FA
concentrations do not increase with storage because FA concentrations were
low even after opening and storage for 3 years on the shelf. This suggests
that FA is a contaminant during the manufacturing process and may vary from
manufacturer to manufacturer and batch to batch. Until further studies are
done to confirm the lack of toxicity to embryos during cryopreservation
(with or without FA scavengers) it may be prudent to screen all batches of
cryoprotectants for FA as part of quality control.
相似文献
12.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献
13.
Fifty women with polycystic ovaries took part in a prospective randomized
study. All women required treatment by in-vitro fertilization (IVF) for
reasons other than anovulation. They had all previously undergone ovarian
stimulation with gonadotrophin therapy which had failed to result in
pregnancy or had been abandoned due to high risk of developing ovarian
hyperstimulation syndrome (OHSS). Twenty-five women were treated by
long-term pituitary desensitization followed by gonadotrophin therapy,
oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent
laparoscopic ovarian electrocautery after pituitary desensitization
followed by gonadotrophin therapy, oocyte retrieval and embryo transfer
(group 2). A significantly higher number of women in group 1 had to have
the treatment cycle abandoned due to impending or actual OHSS, determined
by endocrine and clinical findings. In addition, the development of
moderate or severe OHSS in completed cycles was higher in group 1. The
pregnancy rate and miscarriage rates in the two treatment groups were
similar. The authors propose that laparoscopic ovarian electrocautery is a
potentially useful treatment for women who have previously had an IVF
treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in
a previous treatment cycle.
相似文献
14.
15.
16.
SM Ismail 《Journal of clinical pathology》1993,46(11):1067-1068
17.
Matrix metalloproteinase production by COOH-terminal heparin-binding fibronectin fragment in rheumatoid synovial cells 总被引:6,自引:0,他引:6
Yasuda T Shimizu M Nakagawa T Julovi SM Nakamura T 《Laboratory investigation; a journal of technical methods and pathology》2003,83(2):153-162
Fibronectin with IIICS region is present in rheumatoid synovium, and fibronectin fragments are increased in rheumatoid joints. We investigated the ability of COOH-terminal heparin-binding fibronectin fragment (COOH-HBFN-f) containing IIICS to induce matrix metalloproteinase (MMP) production and the role of mitogen-activated protein kinase (MAPK) pathway and CS-1 sequence that can bind alpha4beta1 integrin in MMP induction by COOH-HBFN-f in rheumatoid synovial fibroblasts (RSF). When RSF in monolayer culture were incubated with COOH-HBFN-f, COOH-HBFN-f stimulated the production of MMP-1, MMP-3, and MMP-13 by RSF in association with activation of extracellular signal-regulated kinase, p38 MAPK, and c-Jun NH(2)-terminal kinase. Immunoprecipitation of cell lysates demonstrated the presence of alpha4 integrin in cultured RSF. Similar to COOH-HBFN-f, treatment with CS-1 synthetic peptide derived from IIICS resulted in increased MMP production and activation of the kinases, although the MMP levels were low. Preincubation of RSF with anti-alpha4 integrin antibody resulted in partial suppression of the COOH-HBFN-f-stimulated MMP production. Inhibition studies using protein kinase inhibitors (PD98059 and SB203580) showed that those MAPK pathways contributed to MMP up-regulation by COOH-HBFN-f and CS-1. Thus, the present results have clearly shown that COOH-HBFN-f and CS-1 stimulate MMP production in association with activation of MAPK pathways in RSF. Integrin alpha4beta1 may be partially involved in the MMP induction by COOH-HBFN-f. 相似文献
18.
重度肥胖患者胃肠分流术后低氧血症机制的分析 总被引:2,自引:0,他引:2
目的 研究重度肥胖对胃肠分流术后动脉血氧分压的影响。方法 对 6 1例进行胃肠分流术的重度肥胖患者及 5 5例择期腹部手术的正常体重患者进行术前肺功能、术前及术后 1~ 5d的血气分析检测。结果 肥胖组术后1~ 5d、对照组术后 1~ 2d的动脉血氧分压较术前显著下降 (P <0 .0 5 ) ;肥胖组术后 1~ 2d动脉血氧分压与其最大分钟通气量及腰臀比显著相关 (P <0 .0 0 0 1)。结论 重度肥胖者较正常体重患者在腹部手术后发生低氧血症的程度较严重且持续时间长。 相似文献
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20.