RESUMO
Background: Duplicate origin of the middle cerebral artery (MCA) is a rare variation of MCA, often mislabeled as the fenestration of the M1 segment of MCA. Case Description: The authors treated an unruptured aneurysm, 8 mm in diameter, associated with a duplicate origin of MCA in a 42-year-old woman who underwent magnetic resonance imaging for transient vertigo. Clipping surgery was inapplicable due to the lack of space to insert clip blades between the neck and two origins of MCA. Under stent-assisted maneuver, the aneurysm sac was successfully obliterated using three coils, resulting in Raymond-Roy class 1 occlusion status. Digital subtraction angiography performed 3 months after the embolization showed complete obliteration of the aneurysm. So far, only 11 patients with aneurysms associated with duplicate origin of MCA have been reported. We performed a literature review of this very rare combination. The size of aneurysms ranged from 2 to 8 mm, with a mean of 5.2 mm. The neck of the aneurysm is mainly located at the corner between the inferior limb and the internal carotid artery. Ours is the youngest and has the largest aneurysm. Conclusion: Aneurysm can arise from duplicate origin of MCA, for which stent-assisted coiling may be an appropriate treatment modality.
RESUMO
The circadian oscillator is generated within the suprachiasmatic nuclei and synchronizes circadian clocks in numerous peripheral tissues. The molecular basis is composed of a number of genes and proteins that form transcriptional and translational feedback loops. Such molecular oscillators are also operative in peripheral tissues, including in the uterus. Although ovarian steroids regulate the function of uterine endometrial stromal cells, the modulation of ovarian steroids on the circadian rhythms remains unknown. Here we investigate the possibility that estradiol (E2) and progesterone (P4) modulate the circadian oscillator of the stromal cells. The study using transgenic rats constructed with Period 2 (Per2) promoter-destabilized luciferase (Per2-dLuc) gene, with the real-time monitoring system of Per2-dLuc oscillation. The stromal cells displayed constant Per2-dLuc oscillation after treatment with dexamethasone, suggesting that the circadian oscillator is operative. However, the circadian oscillator was disrupted by in vivo administration of human chorionic gonadotropin (hCG) following equine chorionic gonadotropin (eCG), although it was altered into a rhythmic pattern 4 days later following hCG. Chronic treatment with P4 induced constant Per2-dLuc oscillation in the stromal cells from eCG-treated immature and pregnant rats, whereas E2 did not promote such a rhythmic Per2-dLuc oscillation. Collectively, P4 synchronizes the circadian oscillator of the uterus endometrial stromal cells through transcriptional and translational feedback loops of the clockwork system.
