Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Proceed order?

Export
  • 1
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] A basic doctrine of reproductive biology is that most mammalian females lose the capacity for germ-cell renewal during fetal life, such that a fixed reserve of germ cells (oocytes) enclosed within follicles is endowed at birth. Here we show that juvenile and adult mouse ovaries possess mitotically ...
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: Relation between retinal melatonin and corneal mitotic rhythms in the Japanese quail was investigated in experiments manipulating the ocular physiology by treatments with formoguanamine hydrochloride (FG) and eye-lid suture. In experiment 1, we investigated the effects of FG, which is known to induce photoreceptor degeneration, on retinal melatonin and corneal mitotic rhythms. FG-treatment completely abolished the retinal melatonin rhythms in both LD 12: 12 and constant darkness (DD), but the corneal mitotic rhythm was maintained with high mitotic rate in darkness under a LD cycle and subjective night under DD. The result suggests that 1) the photoreceptor cells in the retina are the site for melatonin production and/or for the oscillator which drives the circadian rhythm in retinal melatonin, and 2) melatonin is not involved in generation of the corneal mitotic rhythm. In experiment 2, we investigated the effects of eye-lid suture, which is known to induce eye enlargement and bulgy cornea, on the retinal melatonin and corneal mitotic rhythms. Eye-lid suture abolished the corneal mitotic rhythm in both LD and DD, with a high mitotic rate being maintained throughout 24 hr. But retinal melatonin maintained its rhythm with high levels in darkness under a LD cycle and in subjective night under DD. The result suggests that 1) bulgy cornea in the sutured eye was induced by the increase in mitotic rate in the light period, and 2) disappearance of the corneal mitotic rhythm does not have a relation to retinal melatonin. These results suggest that retinal melatonin is not involved in generation of the corneal mitotic rhythm and that there are two circadian clock systems in the eye.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-7330
    Keywords: Apoptosis ; CD44 ; human ; hyaluronic acid ; granulosa cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: This study was designed to examine whether hyaluronicacid (HA) inhibits apoptosis in cumulus and muralgranulosa cells and to examine whether this effect of HAwas mediated through CD44. Methods: Mural and cumulus granulosa cells were obtainedfrom in vitro fertilization patients. The cells were culturedwith various concentrations of HA or HA plus variousconcentrations of anti-CD44 antibody without serum supplement.After 24 hr of culture, the cells were fixed and stainedwith Hoechst 33258. One thousand granulosa cells of eachconditions were observed by fluorescence microscopy. Results: HA inhibited apoptosis in both kinds of granulosacells, and anti-CD44 antibody prevented this effect of HA.Conclusions: The incidence of apoptotic granulosa cellswith fragmented condensed nuclei was reduced by HA viaCD44.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-7330
    Keywords: Aging ; apoptosis ; granulosa cells ; in vitro fertilization ; oocyte quality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: The objective was to determine the effects of women'sage on the ovarian fecundity as assessed by the incidenceof apoptotic granulosa cells. Methods: Twenty-eight normo-ovulatory women underwentovulation induction for standard IVF. The husbands of thesewomen showed severe male infertility factors. The womenwere divided into four groups according to their ages. Womenunderwent follicle aspiration after the administration ofhuman menopausal gonadotropin plus human chorionicgonadotropin. The nuclei of granulosa cells were examinedby using fluorescence microscopy, and the incidence of apoptotic granulosa cells was tabulated. Results: Granulosa cells in the older women revealed asignificant increase in the number of apoptotic cells. Thenumber of total oocytes and the number of mature oocytesobtained significantly decreased with age. However, endometrial thickness and follicular estradiol, progesterone, andfree testosterone levels were not significantly different amongfour different age groups. Conclusions: Age increases apoptotic changes in granulosacells and consequently decreases the ovarian fecundity.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-7330
    Keywords: apoptosis ; controlled ovarian hyperstimulation ; granulosa cells ; in vitro fertilization ; oocyte quality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: The aim was to investigate which ovarian hyperstimulation protocol performed in the same patients causes development of oocytes of good quality. Methods: Twenty normo-ovulatory women underwent three different controlled ovarian hyperstimulation protocols for in vitro fertilization–embryo transfer. Patients underwent follicle aspiration after administration of human chorionic gonadotropin (hCG). The total number of retrieved oocytes, the number of mature oocytes, and the rate of mature oocytes were examined. Recovered granulosa cells were stained with Hoechst 33258 and examined by fluorescence microscopy to estimate the incidence of apoptotic cells. Results: The total number of oocytes and the number of mature oocytes in gonadotropin-releasing hormone agonist (GnRHa) + human menopausal gonadotropin (hMG) + hCG and hMG + hCG cycles were higher than those in the natural cycle (P 〈 0.0001). The rate of mature oocytes in hMG + hCG cycle was the highest among the three protocols (P 〈 0.04). In the mural granulosa cells, the incidence of apoptotic cells in the GnRHa + hMG + hCG cycle was significantly higher than those of the natural (P 〈 0.002) and hMG + hCG cycles (P = 0.0002). The incidence of apoptotic cumulus granulosa cells in the GnRHa + hMG + hCG cycle was significantly higher than those of natural and hMG + hCG cycles (P 〈 0.002). Moreover, the incidence of apoptotic cumulus granulosa cells in the hMG + hCG cycle was significantly lower than that in the natural cycle (P 〈 0.01). Conclusions: These results indicated that hMG + hCG is the most appropriate controlled ovarian hyperstimulation protocol among the three examined with regard to oocyte quality.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...