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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
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MW Lieberman R Barrios G Kala SV Kala ED Lykissa CN Ou 《Environmental health perspectives》1999,107(9):A444-A445
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165 相似文献
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Electrophysiological Response to Ethanol in P and NP Rats 总被引:1,自引:0,他引:1
C. L. Ehlers R. I. Chaplin L. Lumeng T. K. Li 《Alcoholism, clinical and experimental research》1991,15(4):739-744
Event-related potentials (ERPs) have been successfully used in human subjects to evaluate alcoholics as well as those at risk for the future development of alcoholism. In the present study, two lines of rats, those with a preference for ethanol consumption (P) and those not preferring (NP) to drink ethanol were studied using ERP-producing stimuli. Rats were implanted with electrodes in the frontal cortex and dorsal hippocampus (DHPC). A passive auditory "oddball" paradigm was used to record ERP responses following saline and two doses (0.5, 1.0 g/kg) of ethanol. P and NP rats differed under the saline condition in that P rats had smaller N1-like ERP components and larger P2 waves in both cortex and hippocampus. P and NP rats were also found to differ in response to ethanol administration. NP rats evidenced dose-dependent reductions in ERP component amplitudes such as the N1 recorded from cortical sites. P rats did not have such reductions in N1 amplitudes and in fact, displayed increased N1 amplitudes in hippocampal sites. These studies provide further electrophysiological evidence that rats with a genetically influenced preference for ethanol consumption differ from nonpreferring rats at baseline and have a less intense depressant or more stimulating response to ethanol challenge. 相似文献
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Kangaroo Care with a ventilated preterm infant 总被引:4,自引:0,他引:4
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Modulation of in vitro eosinophil progenitors by hydrocortisone: role of accessory cells and interleukins 总被引:1,自引:0,他引:1
The growth of human eosinophil progenitors (CFU-Eo) and the modulation of growth by hydrocortisone were studied as functions of the presence of lymphocytes and monocytes in marrow cells under study; and the source of colony-stimulating factors, specifically, media conditioned by macrophage-like cell line, GCT; phytohemagglutinin-stimulated mononuclear cells (PHA-LCM); or the T cell line, MO. CFU-Eo growth was greatest in marrow containing accessory cells as compared to marrow depleted of accessory cells; and in marrow treated with phytohemagglutinin-stimulated leukocyte conditioned media (PHA-LCM) or MO (T cell line)-conditioned medium (MO-CM) as compared with GCT cell- conditioned medium (GCT-CM). Hydrocortisone reproducibly inhibited eosinophil progenitor growth in unfractionated marrow stimulated by GCT- CM. This effect was abrogated by admixing irradiated mononuclear cells or T lymphocytes with the target marrow or by adding interleukin 1 or interleukin 2 (IL-1, IL-2). Inhibition by hydrocortisone did not occur when monocyte and T lymphocyte depleted marrow was studied. Unlike GCT- CM, MO-CM and PHA-LCM stimulated equal proportions of eosinophil progenitors in nondepleted and accessory cell-depleted marrow and demonstrated less hydrocortisone inhibition. However, both GCT-CM and PHA-LCM produced in the presence of hydrocortisone stimulated significantly fewer CFU-Eos in both unfractionated and accessory cell- depleted marrow target populations. These results indicate that the growth of CFU-Eo and inhibition of growth by hydrocortisone is a direct function of a monocyte-T cell interaction and probably is mediated through effects on the production/release of eosinophil colony stimulating factor (Eo-CSF). 相似文献