Protein tyrosine kinases are enzymes that are capable of adding a phosphate group to specific tyrosines on target proteins. A receptor tyrosine kinase (RTK) is a tyrosine kinase located at the cellular membrane and is activated by binding of a ligand via its extracellular domain. Protein phosphorylation by kinases is an important mechanism for communicating signals within a cell and regulating cellular activity; furthermore, this mechanism functions as an "on" or "off" switch in many cellular functions.
View Article and Find Full Text PDFNasal bleeding is a major complication that can occur during and after transsphenoidal surgery (TSS) for intra- and suprasellar tumors. In most cases, the cause of this bleeding can be attributed to a branch of the maxillary artery called the sphenopalatine artery, injury to which can lead to life-threatening situations. Upon exposure of the suprasellar region and planum sphenoidale during surgery, it is also important to avoid damaging the posterior ethmoidal artery (PEA), a branch of the ophthalmic artery.
View Article and Find Full Text PDFBackground: Arachnoid cysts (ACs) are congenital anomalies of the central nervous system and arise in virtually all locations where the arachnoid membrane exists. Posterior fossa ACs are considered to develop in the posterior aspect of the rhombencephalic roof plate and do not communicate freely with the fourth ventricle or perimedullary subarachnoid space. Although posterior fossa ACs have been reported a number of times, ACs arising from the foramen of Magendie are very rare.
View Article and Find Full Text PDFThe Notch signal regulates both cell viability and apoptosis, and maintains stemness of various cancers including glioblastoma (GBM). Although Notch signal inhibition may be an effective strategy in treating GBM initiating cells (GICs), its applicability to the different subtypes of GBM remains unclear. Here, we analyzed the effectiveness of MRK003, a preclinical γ-secretase inhibitor, on GICs.
View Article and Find Full Text PDFA 42-year-old woman presented with right oculomotor, abducens, and trigeminal palsy. Neuroimaging revealed a small lesion in the right cavernous sinus mimicking meningioma. Because the symptoms gradually worsened, the patient underwent an endoscopic endonasal transsphenoidal surgery for tumor biopsy.
View Article and Find Full Text PDFBackground: Subgaleal hematomas frequently occur in children after head trauma and extend over the cranial sutures. Although conservative treatment suffices in most cases, surgical removal of a subgaleal hematoma is indicated when the patient presents with anemia and headache associated with its progressive enlargement.
Case Description: We present the case of a 7-year-old boy who was medicated with warfarin and aspirin due to a hypoplastic left ventricle and fell from a rock wherein he hit his head in the frontal region.
We experienced an unusual case of a 15-year-old girl who suffered acute bilateral blindness caused by a frontal lobe tumour. She underwent emergent operation, after which her vision recovered. This case emphasizes that a brain mass can cause sudden onset blindness and an emergency intervention might save the patient's sight.
View Article and Find Full Text PDFHyperintense lesions around the resection cavity on magnetic resonance diffusion-weighted imaging (MR-DWI) frequently appear after brain tumor surgery due to the damage of surrounding brain. The putative connection between the lesion and the prognosis for patients with glioblastoma (GBM) was explored. This retrospective study reviewed consecutive sixty-one patients with newly diagnosed GBM.
View Article and Find Full Text PDFObjective: The arcuate fasciculus has been recognized as an important pathway for language processing. Brain tumors located in proximity to the fasciculus frequently cause preoperative language impairment, and in some cases, no language recovery occurs after tumor resection. No predictive value has been presented for possible postoperative language recovery after tumor resection.
View Article and Find Full Text PDFGlioblastoma (GBM) is one of the most lethal malignancies in humans, and novel therapeutic strategies are urgently required for its treatment. Tyrosine kinases (TKs) play a pivotal role in intercellular signal transduction and regulate crucial processes of tumor cell biological activities in GBM. This information provides the basis for the molecular target therapies for GBMs.
View Article and Find Full Text PDFGlioma, the most common primary brain tumor, is characterized by proliferative-invasive growth. However, the detailed biological characteristics of invading glioma cells remain to be elucidated. A monoclonal antibody (clone HMab-1) that specifically and sensitively recognizes the isocitrate dehydrogenase-1 (IDH1) protein carrying the R132H mutation can identify invading glioma cells by immunostaining.
View Article and Find Full Text PDFBackground: Posterior fossa arachnoid cysts, including quadrigeminal cistern arachnoid cysts, can occasionally cause compression of the quadrigeminal plate, leading to Sylvian aqueduct stenosis and induction of cerebellar tonsillar descent into the foramen magnum. This, in turn, can result in obstructive hydrocephalus. In such cases, the characteristic of hydrocephalus is generally considered to be hypertensive.
View Article and Find Full Text PDFBackground: Extensive evidence implicates the Eph receptor family of tyrosine kinases and its ligand, ephrin, in glioma invasion, but it remains incompletely understood how these receptors affect chemotactic behavior of glioma. We sought to identify the Eph family members that correlate with patients' survival and to reveal the function of Eph in glioma invasion.
Methods: Clinical relevance of EphB genes was confirmed in a clinically annotated expression data set of 195 brain biopsy specimens.
Nonenhancing intrinsic brain tumors have been empirically treated with a strategy that has been adopted for World Health Organization (WHO) grade II gliomas (low-grade gliomas: LGGs), even though small parts of the tumors might have been diagnosed as WHO grade III gliomas after surgery. However, the best surgical strategy for nonenhancing gliomas, including LGGs, is still debatable. LGGs have the following features: slow growth, high possibility of histologically malignant transformation, and no clear border between the tumor and adjacent normal brain.
View Article and Find Full Text PDFBackground: Patients with Chiari malformation type I (CM-I) can manifest neurological symptoms, such as headache, neck pain, dysesthesia, swallowing disturbance, and paresis, which are usually stable or slowly progressive even if syringomyelia is coexistent. In some instances, however, acute onset of neurological symptoms has been reported but the pathogenetic mechanism and subsequent clinical course have not been explained. In those cases, it was reported that urgent treatment of foramen magnum decompression (FMD) was very effective.
View Article and Find Full Text PDFGlycogen synthase kinase 3β (GSK3β) is a serine/threonine protein kinase involved in human cancers including glioblastoma. We have previously demonstrated that GSK3β inhibition enhances temozolomide effect in glioma cells. In this report, we investigated the molecular mechanisms of sensitization of glioblastoma cells to temozolomide by GSK3β inhibition, focusing on O(6)-methylguanine DNA methyltransferase (MGMT) gene silencing.
View Article and Find Full Text PDFWe treated a case of recurrent glioblastoma (GBM) with bevacizumab and assessed its effect biologically. A 55-year-old man with a left frontal lobe GBM was experiencing recurrence 7 months postoperation. We administered bevacizumab concomitant with temozolomide (TMZ).
View Article and Find Full Text PDFBackground: The concept of human brain reorganization due to slow-growing lesions, including low-grade glioma, has been gradually and generally accepted. However, few cases have been reported in which the reorganization, especially in the topographic pure primary motor cortex, was observed during brain surgery. We report a case of slow-growing oligodendroglioma located in the pure primary motor cortex, as detected by magnetic resonance imaging that could be resected in part thanks to the brain plasticity.
View Article and Find Full Text PDFSchwannomas of the orbit are very rare benign neoplasms. Intraorbital cystic schwannomas originating from the frontal nerve are even rarer, with only 1 case reported to date. This is most likely due to the fact that, in most cases, the origin of the orbital schwannoma cannot be identified intraoperatively.
View Article and Find Full Text PDFMolecular targeted therapy can potentially provide more effective treatment for patients with high-grade gliomas. Notch and Akt are notable target molecules as they play important roles in a variety of cellular processes, such as regeneration, differentiation, proliferation, migration, and invasion. Here, we assessed the therapeutic possibility of inhibiting Notch and Akt in gliomas using the clinically available, selective small molecule inhibitors MRK003 and MK-2206.
View Article and Find Full Text PDFAwake surgery for lesions in the non-dominant parietal lobe is rare. We report two cases of right parietal lobe glioma for which awake surgery was performed in order to avoid ataxie optique and hemispatial neglect due to injury in the superior and inferior parietal lobule, respectively. Among several tests to assess the dysfunction of spatial recognition, line bisection test was selected for the task during awake surgery because of its simplicity, easy repetition, and utility.
View Article and Find Full Text PDFA 63-year-old woman presented with dizziness followed by gait disturbance and loss of appetite. Magnetic resonance image (MRI) showed that a lesion located in the medulla oblongata, appearing as hyperintense on T2-weighted image and with slight enhancement area, appeared in the ventral aspect of the mass on T1-weighted MR imaging with gadolinium. It was diagnosed as high-grade brain-stem glioma and the patient underwent chemoradiotherapy.
View Article and Find Full Text PDFObject: Disturbance of the arcuate fasciculus in the dominant hemisphere is thought to be associated with language-processing disorders, including conduction aphasia. Although the arcuate fasciculus can be visualized in vivo with diffusion tensor imaging (DTI) tractography, its involvement in functional processes associated with language has not been shown dynamically using DTI tractography. In the present study, to clarify the participation of the arcuate fasciculus in language functions, postoperative changes in the arcuate fasciculus detected by DTI tractography were evaluated chronologically in relation to postoperative changes in language function after brain tumor surgery.
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