The musk shrew, Suncus murinus, is an induced ovulator, the cumulus oophorus of which is unusual in several respects: it has no matrix, it always induces the acrosome reaction and it appears to be essential for fertilization. The present study documents distinctive features of the cumulus oophorus before and after ovulation, and of copulation-induced maturation of the ovulatory follicle, which ...

This study investigated the participation of MAPK in the resumption of meiosis [germinal vesicle breakdown (GVB)] in oocytes and cumulus expansion using oocyte-cumulus cell complexes (OCC) from Mos-null mice (Mos(tm1Ev)/Mos(tm1Ev), hereafter Mos(-/-)). MAPK activity was not detected in Mos(-/-) oocytes whether they matured in vivo or in vitro, with or without gonadotropin stimulation. Therefore...

The process of cumulus mucification in pig preovulatory follicles was examined by scanning electron microscopy. The localization of extracellular material and changes in the granulosa cell surface were observed at 0, 16, 20 and 40 h after hCG injection. At 0 h the pig oocyte cumulus complex was closely attached to the parietal layer of granulosa cells. Cumulus and parietal granulosa cells had m...

The aim of this study was to investigate cumulus expansion, nuclear maturation and expression of connexin 43, cyclooxygenase-2 and FSH receptor transcripts in equine cumuli oophori during in vivo and in vitro maturation in the presence of equine FSH (eFSH) and precursors for hyaluronic acid synthesis. Equine cumulus-oocyte complexes (COC) were cultured in a control defined medium supplemented w...

Photoluminescence of Monolayer MoS2 The Ti-doped monolayers with ultra-high photoluminescence (PL) intensity are successfully synthesized through chemical vapor transport as reported in article number 2200431 by Zhao Ma, Hailong Qiu, and co-workers. PL from the is 85-fold stronger than that pristine MoS2. giant enhancement attributed to dopant-induced O-Ti-S units improved interaction between m...

in CO/Ag/Pt(111) surfaces the interaction between Ag and Pt enhances the strength of the Ag-CO bond. The CO desorption temperature of one monolayer of silver supported on Pt(11 !) is ~ 70 K higher than that of Ag(111). Our results indicate that the infrared intensities of adsorbed CO are not representative of the relative composition of Pt(l 11) surfaces containing submonolayer coverages of sil...

Bidirectional communication between oocytes and the companion granulosa cells is essential for the development and functions of both compartments. Oocytes are deficient in their ability to transport certain amino acids and in carrying out glycolysis and cholesterol biosynthesis. Cumulus cells must provide them with the specific amino acids and the products in these metabolic pathways. Oocytes c...

Studies aimed at the influence of smoking on reproductive functions have found out fertility disorders in smokers occurring at any stage of reproductive processes. In our experiments the role of cadmium, nicotine and anabasine was investigated in the expansion of oocyte-cumulus complexes (OCC) isolated from large antral porcine follicles. Suppression of FSH-induced cumulus expansion and signifi...

OBJECTIVE To investigate the effects of recombinant (r-) LH supplementation in "low responder" patients undergoing ovarian stimulation with r-FSH for an IVF program. The apoptosis rate in cumulus cells was used as an indicator of oocyte quality. DESIGN Comparison of the rate of DNA fragmentation and caspase-3 activity in cumulus cells in women stimulated with r-LH and r-FSH, versus patients t...

The addition of alpha-amanitin to extrafollicular, cumulus-enclosed ovine oocytes at explantation inhibits meiotic maturation and prevents many of the changes in protein synthesis that normally accompany maturation. By contrast, these inhibitory effects are considerably reduced by either delaying the addition of the drug for 1-4 h or by denuding the oocytes of all associated cumulus cells at th...