The Novel Pig In Vitro Maturation System to Improve Developmental Competence of Oocytes Derived from Atretic Non-Vascularized Follicle.

The in vitro maturation (IVM) technique is beneficial for producing animal offspring, but the blastocyst rate is low after IVM. In this technique, cumulus-oocyte complexes (COCs) are collected from medium size follicles. The follicles are ultimately selected as large dominant follicles or atretic follicles; therefore it is possible that the COCs collected using IVM are contaminated by follicles that will develop into large follicles and induce atresia. In the dominant follicles, estradiol-17beta and progesterone induce the differentiation of follicular somatic cells which exhibit the ability to respond to ovulation during follicular development. Thus, we hypothesized that changes in the hormonal condition of healthy follicles are essential for oocyte maturation during IVM. In this study, we performed a comparative analysis of the steroid hormone concentrations in non-vascularized follicles (NVFs) and vascularized follicles (VFs). The estradiol-17beta concentration increased in medium VFs, whereas the level was low in NVFs of the same size. The progesterone concentration increased with large follicular size in VFs, but the level remained low in follicles of any size among NVFs. To improve the oocyte quality derived from NVFs, NVF COCs were cultured with FSH alone or FSH under theVF hormonal conditions. Cultivation under the VF hormonal conditions dramatically improved the proliferation and survival of cumulus cells, meiotic maturation of oocytes, cumulus expansion, and blastocyst rate following in vitro fertilization. Thus, the cultivation of NVF COCs under VF hormonal conditions improves the developmental potential to the blastocyst stage by NVF oocytes.

[A case of amnesia caused by a subcortical hematoma in the left retrosplenial region].

A 54-year-old right-handed woman suffered transient aphasia and persistent amnesia caused by a subcortical hematoma in the left occipital lobe. She appeared to have aphasia, although it disappeared within 3 weeks. It is noteworthy that she had a lesion in the left retrosplenial region but exhibited both verbal and non-verbal memory impairment. However, her intelligence, remote memory and digit span were normal. She had no topographic disturbance. Computed tomography and magnetic resonance imaging revealed a subcortical hematoma in the left occipital lobe including the retrosplenial region. Single photon emission CT showed a low perfusion area in the retrosplenial region and in the left thalamus. We concluded that the retrosplenial amnesia might be caused by the interruption of hippocampal input into the anterior thalamus.