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71.
Notch signaling plays an essential role in development as well as cancer. We have previously shown that Notch3 is important for lung cancer growth and survival. Notch receptors are activated through the interaction with their ligands, resulting in proteolytic cleavage of the receptors. This interaction is modulated by Fringe, a family of fucose-specific β1,3 N-acetylglucosaminyltransferases that modify the extracellular subunit of Notch receptors. Studies in developmental models showed that Fringe enhances Notch’s response to Delta ligands at the expense of Jagged ligands. We observed that Manic Fringe expression is down-regulated in lung cancer. Since Jagged1, a known ligand for Notch3, is often over-expressed in lung cancer, we hypothesized that Fringe negatively regulates Notch3 activation. In this study, we show that re-expression of Manic Fringe down-regulates Notch3 target genes HES1 and HeyL and reduces tumor phenotype in vitro and in vivo. The mechanism for this phenomenon appears to be related to modulation of Notch3 protein stability. Proteasome inhibition reverses Manic Fringe-induced protein turnover. Taken together, our data provide the first evidence that Manic Fringe functions as a tumor suppressor in the lung and that the mechanism of its anti-tumor activity is mediated by inhibition of Notch3 activation. 相似文献
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Nguyen Van Quan Tran Dang Xuan Hoang-Dung Tran Ateeque Ahmad Tran Dang Khanh Tran Dang Dat 《Saudi Pharmaceutical Journal》2019,27(5):643-649
This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic α-amylase and α-glucosidase which were significantly higher than γ-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC50 values of 921.55 and 884.03 µg/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 µg/g dry weight) and MB (6.24 µg/g dry weight) in rice bran were determined. Findings of this study revealed the α-amylase, α-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran. 相似文献
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Liang Jiang Xiao Guang Liu Hui Shu Yuan Shao Min Yang Jie Li Feng Wei Chen Liu Lei Dang Zhong Jun Liu 《The spine journal》2014,14(6):944-954
Background contextVertebral hemangiomas (VHs) are called benign tumors but are actually just vascular malformations. The diagnosis and treatment for aggressive VHs is still controversial, due to their rarity.PurposeTo evaluate the safety and efficiency of the present diagnostic methods and treatment choices.Study designA retrospective study of aggressive VHs with neurologic deficit.Patients sampleA total of 29 consecutive aggressive VH cases were diagnosed and treated in our department since 2001.Outcome measuresWe routinely took anteroposterior and lateral spinal roentgenograms, computed tomography, and magnetic resonance images.MethodsTrocar biopsy is indicated in suspected malignant cases. Radiotherapy was usually our first choice if the neurologic deficit was mild or developed slowly. Surgery was indicated if the neurologic deficit was severe or developed quickly or if the radiotherapy was not effective.ResultsThis series included 12 males and 17 females, and the mean age at diagnosis was 44.0 years (range, 21–72 years). Ten patients had radiculopathy, 1 had cauda equina syndrome, and 18 cases had myelopathy. Twenty-one cases had lesions in the thoracic spine, 5 in the lumbar, and 3 in the cervical region. Eleven cases had untypical image findings, including five cases with pathologic vertebral fracture. The neurologic compression came from only epidural soft tumor mass in 18 cases, whereas it came from both bony compression and soft lesion in the other 11 cases. Ten cases had radiotherapy alone, but two failed and had surgery later. Twenty-one cases had surgery. In the 12 cases having surgical decompression without vertebroplasty, the average estimated blood loss was 1900 mL, and it was 1093 mL for the eight cases having decompression with vertebroplasty. The average follow-up was 51.1 months (range, 24–133 months). There was no recurrence in those cases with radiotherapy, whereas three had local recurrence in those six cases treated by surgical decompression alone without radiotherapy.ConclusionsIn aggressive VHs, epidural soft-tissue compression was usually the main reason for neurologic deficit. In cases with rapid progressive and/or severe myelopathy, posterior decompression and stabilization could be combined with intraoperative vertebroplasty to reduce blood loss. 相似文献
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Newly-found functions of metformin for the prevention and treatment of age-related macular degeneration 下载免费PDF全文
AIM: To explore the temporal mitochondrial characteristics of retinal pigment epithelium (RPE) cells obtained from human embryonic stem cells (hESC)-derived retinal organoids (hEROs-RPE), to verify the optimal period for using hEROs-RPE as donor cells from the aspect of mitochondria and to optimize RPE cell-based therapeutic strategies for age-related macular degeneration (AMD). METHODS: RPE cells were obtained from hEROs and from spontaneous differentiation (SD-RPE). The mitochondrial characteristics were analyzed every 20d from day 60 to 160. Mitochondrial quantity was measured by MitoTracker Green staining. Transmission electron microscopy was adopted to assess the morphological features of the mitochondria, including their distribution, length, and cristae. Mitochondrial membrane potentials (MMPs) were determined by JC-1 staining and flow cytometry. ROS levels were evaluated by flow cytometry, and ATP levels were measured by a luminometer. Differences between two groups were analyzed by the independent-samples t-test, and comparisons among multiple groups were made using one-way ANOVA or Kruskal-Wallis H test when equal variance is not assumed. RESULTS: hEROs-RPE and SD-RPE cells from day 60 to 160 were successfully differentiated from hESCs and expressed RPE-specific markers (Pax6, mitf, Bestrophin-1, RPE65, Cralbp). RPE features, including a cobblestone-like morphology with tight junctions (ZO-1), pigments and microvilli, were also observed in both hERO-RPE and SD-RPE cells. The mitochondrial quantities peaked in both hEROs-RPE and SD-RPE cells at day 80. However, the cristae of hEROs mitochondria were less mature and abundant than those of SD mitochondria at day 80, with hEROs mitochondria becoming mature at day 100. Both hEROs-RPE and SD-RPE cells showed low ROS levels from day 100 to 140 and maintained a normal MMP during this period. However, hEROs mitochondria maintained a longer time to produce high levels of ATP (from day 120 to 140) than SD-RPE cells (only day 120). CONCLUSION: Mitochondria of hEROs-RPE cells develop slower and maintain a longer time to supply high-levels of energy than SD-RPE cells. From a mitochondrial aspect, hEROs-RPE cells from day 100 to 140 are an optimal cell source for treating AMD. 相似文献
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目的 汉化进食障碍患者家庭顺应量表,并检验其信效度。方法 根据Brislin翻译模式将量表翻译成中文,通过专家函询和预调查对量表进行文化调适和修订。将量表应用于300例进食障碍患者照顾者检验信效度。结果 中文版进食障碍患者家庭顺应量表的量表水平内容效度指数为0.918。探索性因子分析结果显示5个因子可解释总变异量的49.862%。量表的各维度得分与量表总分呈中高度相关,各维度得分之间呈中低度相关或不相关。量表总Cronbach′s α为0.877,重测信度为0.883。结论 中文版进食障碍患者家庭顺应量表具有较好的信效度,可用于测量进食障碍患者的家庭顺应情况。 相似文献
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Jin-hu Fan BS Wan-yi Sun MS Huan Yang PhD Xiao-kun Wang MS Christian C. Abnet PhD You-lin Qiao MD PhD 《Cancer》2023,129(15):2360-2372