Cover Story :
Recently, the effects of macromolecular crowding on cultured cells have gathered increasing interest. Crowded culture medium prepared by the addition of polyvinylpyrrolidone (PVP; Mw 360,000) positively influences the viability of oocytes during in vitro growth. Mizumachi et al. found that crowding affects a wide range of factors, including oocyte viability, complex morphology, and intimate conjunction of oocytes with cumulus/granulosa cells across the zona pellucida (Mizumachi et al. Macromolecular crowded conditions strengthen contacts between mouse oocytes and companion granulosa cells during in vitro growth, pp. 153-160). Confocal laser scanning microscopy indicated a higher number of transzonal processes (TZPs) reaching the oocyte from cumulus cells in 2% PVP medium than in 0% PVP medium.
Cover Story :
Whether cumulus cells are required for the successful vitrification of mature oocytes in cattle is controversial. Ishii et al. re-evaluated the effects of the presence of multi-layered cumulus cells (MCCs) on the vitrification of mature bovine oocytes (Ishii et al., Embryogenesis of vitrified mature bovine oocytes is improved in the presence of multi-layered cumulus cells. pp. 95–99). In the presence of MCCs, there was no difference between the embryonic development of fresh and vitrified mature bovine oocytes. These results suggest that MCCs protect mature oocytes from freezing, and promote their survival and development after in vitro fertilization. Ishii et al. successfully produced calves using a small number of vitrified mature oocytes with MCCs collected from the ovaries of individual cows post-slaughter.
Cover Story :
Okuyama et al. reported a transvaginal endoscopy-based technique for conducting ovarian examination in sows in a standing position. Sows were sedated in pig stalls, and their vaginal walls were punctured. Subsequently, a urethroscope was inserted into their abdomen, and an examination was conducted after their ovaries had moved towards the urethroscope camera via rectal palpation (Okuyama MW, et al. A transvaginal endoscopy-based technique for performing ovarian examinations in sows. pp. 617–622). This less invasive procedure without the use of general anesthesia may allow repeated ovarian examinations and increase our understanding of the ovarian dynamics in pigs.
Monitoring Metabolic Health of Dairy Cattle in the Transition Period
Released: August 10, 2010 | Volume 56 Issue S Pages S29-S35
Mammary Growth and Regression -Regulation of Milk Synthesis-
Released: October 20, 2010 | Volume 42 Issue 6 Pages j143-j150
Reconsidering the roles of endogenous estrogens and xenoestrogens: the membrane estradiol receptor G protein-coupled receptor 30 (GPR30) mediates the effects of various estrogens
Released: March 06, 2018 |
Article ID 2017-153
Hiroya KADOKAWA, Kiran PANDEY, Kereilwe ONALENNA, Asrafun NAHAR
Follicular Growth and Atresia in Mammalian Ovaries: Regulation by Survival and Death of Granulosa Cells
Released: March 22, 2012 | Volume 58 Issue 1 Pages 44-50
Fuko MATSUDA, Naoko INOUE, Noboru MANABE, Satoshi OHKURA