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Background contextLumbar intradural disc herniation (IDH) is rare, and intradural cyst associated with IDH is quite rare. Only seven cases of an intradural cyst associated with lumbar disc herniation have been reported, and all were gas-filled cysts. We report the first case, to our knowledge, of a fluid-filled intradural cyst associated with IDH.PurposeTo report an extremely rare case of a fluid-filled intradural cyst associated with lumbar IDH and suggests the possible pathogenesis.Study designCase report.MethodsAn 82-year-old woman presented with right leg pain and motor weakness. Computed tomography and magnetic resonance imaging (MRI) scans showed calcified lumbar disc herniation and an intradural cystic mass at the L1–L2 level. An MRI, which was performed 2 years before admission, showed an IDH without a cyst at the same level.ResultsSurgical resection of the intradural cyst was performed. Intraoperative finding showed a fluid-filled intradural cyst with 1-cm diameter of displacing nerve rootlets. The cyst was connected with extradural cystic components through a ventral dural hole, but the tract was blocked by fibrous septum. Histopathologic examination showed a pseudocyst that consisted of degenerative cartilaginous and fibrous tissues, including degenerative disc materials. We concluded that the cyst was an intradural cyst transformed from the intradural disc fragment.ConclusionsThe current case is the first report to our knowlege of a fluid-filled intradural cyst associated with IDH. The possible mechanism may be focal degeneration and spontaneous absorption of the intradural disc with fluid production. Unlike the gas-filled intradural cysts, the cause of the pure fluid-filled cyst may be disconnection from the intervertebral vacuum because of a calcified disc and septation of the cyst.  相似文献   
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DNMT3A, a DNA methyltransferase that functions for de novo methylation, is important in development and many cellular processes related to tumorigenesis. Somatic mutations of DNMT3A gene, including recurrent mutations in its Arg‐882, were recently reported in acute myelogenous leukemia (AML), strongly suggesting its role in development of AML. To see whether DNMT3A mutation occurs in other malignancies as well, we analyzed DNMT3A in 916 cancer tissues from 401 hematologic malignancies (AML, acute lymphoblastic leukemias (ALL), multiple myelomas and lymphomas) and 515 carcinomas (lung, breast, prostate, colorectal and gastric carcinomas) using a single‐strand conformation polymorphism (SSCP) assay. We identified DNMT3A mutations, especially the Arg‐882 mutations, in adulthood AML (9.4%). In addition, we found DNMT3A mutations in pre‐B‐ALL and three lung cancers at lower frequencies. Allelic loss of DNMT3A was frequently observed in most cancer types analyzed, including lymphomas (48.1%), gastric cancers (23.5%) and lung cancers (18.3%) irrespective of DNMT3A mutation. Also, loss of DNMT3A expression was common in lung cancers (46.4%), and was associated with the allelic loss. Our data indicate that DNMT3A gene is mutated mainly in AML, but it occurs in other cancers, such as ALL and lung cancer, despite the lower incidences. Also, the data suggest that DNMT3A is altered in many cancer types by various ways, including somatic mutations, allelic loss and loss of expression that might play roles in tumorigenesis.  相似文献   
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Cucurbita moschata Duch. has long been used for traditional health food in many countries. However, to enhance the immune system of Cucurbita moschata Duch. and its major component, β-carotene is not clear. Here, we determined the immune enhancement effect of Cucurbita moschata Duch. and β-carotene in mouse splenocytes and RAW 264.7 macrophage cell line. We prepared baked Cucurbita moschata Duch. (Sweetme Sweet PumpkinTM, SSP) and steamed Cucurbita moschata Duch. (SC). Splenocytes isolated from the spleen of BALB/c mice were treated with SSP, SC, and β-carotene for 24?h. RAW 264.7 cells were stimulated with recombinant interferon-γ (rIFN-γ) for 6?h before treatment with SSP, SC, or β-carotene. SSP, SC and β-carotene significantly up-regulated the proliferation of splenocyte and mRNA expression of KI-67. The levels of interleukin-2 and IFN-γ were up-regulated by SSP, SC, or β-carotene in the splenocytes. SC and β-carotene also increased the levels of tumor necrosis factor-α (TNF-α) in the splenocytes. In addition, SSP, SC, or β-carotene significantly increased the levels of TNF-α through the nuclear translocation of the nuclear factor-κB and phosphorylation of IκBα in the rIFN-γ-primed RAW 264.7 cells. These data indicate that Cucurbita moschata Duch. and β-carotene may have an immune-enhancing effect through the production of Th1 cytokines by activation of splenocytes and macrophages.  相似文献   
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