URL: http://www.clinicaltrials.gov. Unique identifier: NCT02251665.
Members of a subclass of hairy/Enhancer of split [E(spl)] homologs, called hesr genes, are structurally related to another subclass of hairy/E(spl) homologs, Hes genes, which play an important role in neural development. To characterize the roles of hesr genes in neural development, we used the retina as a model system. In situ hybridization analysis indicated that all hesr genes are expressed in the developing retina, but only hesr2 expression is associated spatially with gliogenesis. Each member was then misexpressed with retrovirus in the retinal explant cultures prepared from mouse embryos or neonates, which well mimic in vivo retinal development. Interestingly, hesr2 but not hesr1 or hesr3 promoted gliogenesis while inhibiting rod genesis without affecting cell proliferation or death, suggesting that the cells that normally differentiate into rods adopted the glial fate by misexpression of hesr2. The gliogenic activity of hesr2 was more profound when it was misexpressed postnatally than prenatally. In addition, double mutation of the neuronal determination genes Mash1 and Math3, which increases Mü ller glia at the expense of bipolar cells, upregulated hesr2 expression. These results indicate that, among structurally related hesr genes, only hesr2 promotes glial versus neuronal cell fate specification in the retina and that antagonistic regulation between hesr2 and Mash1-Math3 may determine the ratios of neurons and glia.
The authors evaluated adverse effects of intracarotid propofol injection during a Wada test and their risk factors in 58 patients. Nineteen patients had an adverse effect, mostly in patients receiving more than 10 mg. For patients older than age 55 years or those requiring an injection dose greater than 20 mg to produce hemiplegia, propofol should be injected slowly and patients monitored for excitatory movements.
OBJECTIVE Transient neurological symptoms are frequently observed during the early postoperative period after direct bypass surgery for moyamoya disease. Abnormal signal changes in the cerebral cortex can be seen in postoperative MR images. The purpose of this study was to reveal the radiological features of the "cortical hyperintensity belt (CHB) sign" in postoperative FLAIR images and to verify its relationship to transient neurological events (TNEs) and regional cerebral blood flow (rCBF). METHODS A total of 141 hemispheres in 107 consecutive patients with moyamoya disease who had undergone direct bypass surgery were analyzed. In all cases, FLAIR images were obtained during postoperative days (PODs) 1-3 and during the chronic period (3.2 ± 1.13 months after surgery). The CHB sign was defined as an intraparenchymal high-intensity signal within the cortex of the surgically treated hemisphere with no infarction or hemorrhage present. The territory of the middle cerebral artery was divided into anterior and posterior parts, with the extent of the CHB sign in each part scored as 0 for none; 1 for presence in less than half of the part; and 2 for presence in more than half of the part. The sum of these scores provided the CHB score (0-4). TNEs were defined as reversible neurological deficits detected both objectively and subjectively. The rCBF was measured with SPECT using N-isopropyl-p-[I]iodoamphetamine before surgery and during PODs 1-3. The rCBF increase ratio was calculated by comparing the pre- and postoperative count activity. RESULTS Cortical hyperintensity belt signs were detected in 112 cases (79.4%) and all disappeared during the chronic period. Although all bypass grafts were anastomosed to the anterior part of the middle cerebral artery territory, CHB signs were much more pronounced in the posterior part (p < 0.0001). TNEs were observed in 86 cases (61.0%). Patients with TNEs showed significantly higher CHB scores than those without (2.31 ± 0.13 vs 1.24 ± 0.16, p < 0.0001). The CHB score, on the other hand, showed no relationship with the rCBF increase ratio (p = 0.775). In addition, the rCBF increase ratio did not differ between those patients with TNEs and those without (1.15 ± 0.033 vs 1.16 ± 0.037, p = 0.978). CONCLUSIONS The findings strongly suggest that the presence of the CHB sign during PODs 1-3 can be a predictor of TNEs after bypass surgery for moyamoya disease. On the other hand, presence of this sign appears to have no direct relationship with the postoperative local hyperperfusion phenomenon. Vasogenic edema can be hypothesized as the pathophysiology of the CHB sign, because the sign was transient and never accompanied by infarction in the present series.
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