Functional integrity of the auditory brainstem was studied at term in babies born at 30- 36 wk of gestation using maximum length sequence brainstem auditory evoked response (MLS BAER). Compared with normal term babies...Functional integrity of the auditory brainstem was studied at term in babies born at 30- 36 wk of gestation using maximum length sequence brainstem auditory evoked response (MLS BAER). Compared with normal term babies, preterm babies who had perinatal complications showed a tendency of an increase in wave V latency and I- V and III- V intervals at all 91- 910/s clicks, with statistical significance at higher rates. Wave V latency and I- V interval increased significantly at 455/s and 910/s. III- V interval increased at all click rates, which was more significant at higher rates. III- V/I- III interval ratio increased at most rates. Waves III and V amplitudes reduced significantly mainly at 455/s and 910/s. In preterm babies who had no perinatal complications, there were no major MLS BAER abnormalities except an increase in III- V interval at 91- 910/s. By comparison, the preterm babies with perinatal complications had a significant increase in wave V latency, I- V and III- V intervals, and III- V/I- III interval ratio at 455/s and 910/s clicks. These results suggest that although there are no major abnormalities in brainstem auditory function in preterm babies without perinatal complications, the auditory brainstem, mainly the more central part, in preterm babies with perinatal complications is impaired, which becomes more apparent at very high stimulus rates. We conclude that preterm babies with perinatal complications are at high risk of central auditory impairment.展开更多
Meningiomas are the most common primary tumors in central nervous system. While recent studies have revealed genetic clues to lower grade human meningiomas, the molecular determinants driving the progression and recur...Meningiomas are the most common primary tumors in central nervous system. While recent studies have revealed genetic clues to lower grade human meningiomas, the molecular determinants driving the progression and recurrence of anaplastic meningi- oma, the most malignant subtype with a low prevalence but high morbidity, are still poorly understood. It has been proposed that high recurrence rates of malignant meningiomas are linked to cancer stem cells. Indeed, tumor stem-Uke cells have been iso- lated from various meningioma subtypes, but never been obtained from anaplastic meningioma, in this study, we successfully isolated stem-Uke cells from human anaplastic meningioma. These cells are capable of forming spheres and initiating xenograft tumors that recapitulate anaplastic meningioma phenotypes, and thus could serve as an in vitro model for malignant meningi- omas. KLF4, a transcription factor known for its role in sternness maintenance, was identified as one of the most frequently mutated genes in the benign secretory meningioma. Interestingly, we found that KLF4 is downregulated in anaplastic meningi- oma compared with low-grade meningioma subtypes. By manipulating KLF4 expression in anaplastic meningioma stem-like cells, we demonstrated that KLF4 acts as a tumor suppressor during malignant progression in meningioma, affecting apoptosis, prolif- eration, invasion, and cell cycle. These results suggest a potential therapeutic value of KLF4 for clinical intervention of anaplastic meningioma.展开更多
文摘Functional integrity of the auditory brainstem was studied at term in babies born at 30- 36 wk of gestation using maximum length sequence brainstem auditory evoked response (MLS BAER). Compared with normal term babies, preterm babies who had perinatal complications showed a tendency of an increase in wave V latency and I- V and III- V intervals at all 91- 910/s clicks, with statistical significance at higher rates. Wave V latency and I- V interval increased significantly at 455/s and 910/s. III- V interval increased at all click rates, which was more significant at higher rates. III- V/I- III interval ratio increased at most rates. Waves III and V amplitudes reduced significantly mainly at 455/s and 910/s. In preterm babies who had no perinatal complications, there were no major MLS BAER abnormalities except an increase in III- V interval at 91- 910/s. By comparison, the preterm babies with perinatal complications had a significant increase in wave V latency, I- V and III- V intervals, and III- V/I- III interval ratio at 455/s and 910/s clicks. These results suggest that although there are no major abnormalities in brainstem auditory function in preterm babies without perinatal complications, the auditory brainstem, mainly the more central part, in preterm babies with perinatal complications is impaired, which becomes more apparent at very high stimulus rates. We conclude that preterm babies with perinatal complications are at high risk of central auditory impairment.
基金This study was supported by grants from the National Natural Science Foundation of China (81372707, 81072070), Shanghai Committee of Sdence and Technology (15140902200, 16140903000), and the Natural Science Foundation of Shanghai (15ZR1405600).
文摘Meningiomas are the most common primary tumors in central nervous system. While recent studies have revealed genetic clues to lower grade human meningiomas, the molecular determinants driving the progression and recurrence of anaplastic meningi- oma, the most malignant subtype with a low prevalence but high morbidity, are still poorly understood. It has been proposed that high recurrence rates of malignant meningiomas are linked to cancer stem cells. Indeed, tumor stem-Uke cells have been iso- lated from various meningioma subtypes, but never been obtained from anaplastic meningioma, in this study, we successfully isolated stem-Uke cells from human anaplastic meningioma. These cells are capable of forming spheres and initiating xenograft tumors that recapitulate anaplastic meningioma phenotypes, and thus could serve as an in vitro model for malignant meningi- omas. KLF4, a transcription factor known for its role in sternness maintenance, was identified as one of the most frequently mutated genes in the benign secretory meningioma. Interestingly, we found that KLF4 is downregulated in anaplastic meningi- oma compared with low-grade meningioma subtypes. By manipulating KLF4 expression in anaplastic meningioma stem-like cells, we demonstrated that KLF4 acts as a tumor suppressor during malignant progression in meningioma, affecting apoptosis, prolif- eration, invasion, and cell cycle. These results suggest a potential therapeutic value of KLF4 for clinical intervention of anaplastic meningioma.