bluuebunny/crossref_metadata_2025_split huggingface dataset:
Communication between malignant glioma cells and vascular endothelial cells through gap junctions
Authors: Zhang Wei , DeMattia Joseph A. , Song Hua , Couldwell William T. 
Published: May 2009

Object. Extensive invasion and angiogenesis are hallmark features of malignant gliomas. Communication between malignant glioma cells and surrounding astrocytes occurs, resulting in transformation of the astrocytic phenotype. In the present study, the authors examined whether malignant glioma cells and vascular endothelial cells (VECs) communicate through the formation of gap junctions and whether this communication influences angiogenesis.
Methods. Connexin43 (Cx43), a gap junction protein expressed in glioma cells, was identified in human umbilical VECs (HUVECs). Immunocytochemical staining for Cx43 demonstrated immunoreactive plaques at areas of cell—cell contact among HUVECs as well as between HUVECs and Cx43-expressing malignant glioma cells. Dye transfer, performed using the gap junction—permeable dye dicarboxy-dichlorofluorescein diacetate (CDCF), among these cocultures indicated that these were functional communications. Calcium signaling also occurred from malignant glioma cells to HUVECs. Tube formation by HUVECs cocultured with Cx43-transfected T98G malignant glioma cells (T98G-Cx43 cells) or with U87MG malignant glioma cells, which naturally express Cx43, was significantly increased compared with tube formation by HUVECs alone. The difference in tube formation by HUVECs cocultured with empty vector—transfected T98G glioma cells (T98G-mock cells) or with Cx43-deficient U373MG malignant glioma cells and tube formation by HUVECs alone was not statistically significant. Furthermore, the concentration of vascular endothelial growth factor (VEGF), an angiogenic factor important for the induction of angiogenesis and blood vessel formation, was significantly higher in medium harvested from cultures of T98G-Cx43 cells than in that harvested from cultures of control T98G-mock cells. Human malignant glioma U87MG cells also secreted increased concentrations of VEGF as compared with HUVECs alone. Nevertheless, there was no statistically significant difference in tube formation by HUVECs cultured in medium conditioned by either Cx43-expressing or Cx43-deficient glioma cells, suggesting that the direct gap junction communication between glioma cells and HUVECs may play a much more significant role than the increased VEGF secretion in vascular tube formation in this assay.
Conclusions. These results indicate that functional gap junction formation between human malignant glioma cells and VECs occurs. This communication appears to influence tumor angiogenesis. Targeting gap junction signaling may offer a potential mechanism for therapy in patients with these tumors.
High-dose ibuprofen for reduction of striatal infarcts during middle cerebral artery occlusion in rats
Authors: Antezana David F. , Clatterbuck Richard E. , Alkayed Nabil J. , Murphy Stephanie J. , Anderson Lauren G. , Frazier James , Hurn Patricia D. , Traystman Richard J. , Tamargo Rafael J. 
Published: May 2009

Object. Ibuprofen is an antiinflammatory drug that disrupts leukocyte—endothelial cell interactions by limiting expression of endothelial adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), also known as CD54. The authors hypothesized that ibuprofen could reduce the size of the infarct associated with transient focal ischemia by inhibition of ICAM-1 expression, and they evaluated its effects in rats treated with middle cerebral artery (MCA) occlusion. Ibuprofen treatment was compared with mild systemic hypothermia, which is known to be neuroprotective and is commonly used during neurosurgical procedures.
Methods. The maximum ibuprofen dose (240 mg/kg/day) that could be tolerated with no systemic toxicity was established in the initial experiments. In the efficacy experiment, rats were pretreated with vehicle, ibuprofen, or hypothermia (33°C) prior to 2 hours of MCA occlusion; then their brains were harvested at 24 hours of reperfusion for histological studies. End-ischemic cerebral blood flow (CBF) was evaluated using [14C]iodoantipyrine autoradiography in additional cohorts. Expression of ICAM-1 within ischemic compared with nonischemic caudate nucleus and putamen (striatum) or cortex was evaluated using immunohistochemical studies. Compared with vehicle treatment, ibuprofen produced a 46.2% reduction (p = 0.01) in striatal infarcts, which was comparable to hypothermia (48.7% reduction, p = 0.02). Ibuprofen did not alter end-ischemic CBF in any region studied, and the ibuprofen treatment group had the lowest proportion of animals with marked ICAM-1 staining.
Conclusions. Ibuprofen given in maximum tolerated doses reduces the striatal infarct size after focal cerebral ischemia. The neuroprotective mechanism does not work through preservation of intraischemic CBF and is consistent with inhibition of ICAM-1 expression; however, at the doses used in this study, other effects of ibuprofen on platelet and endothelial function are possible.
Juxtaposition of an ectopic corticotroph adenoma of the sphenoid sinus with orthotopic intrasellar corticotroph hyperplasia in a patient with Cushing disease
Authors: Al-Gahtany Mubarak , Bilbao Juan , Kovacs Kalman , Horvath Eva , Smyth Harley S. 
Published: May 2009

✓ Ectopic pituitary adenomas (EPAs) are rare and their association with orthotopic corticotroph hyperplasia has not been published.
The case of a 30-year-old woman with clinical and biochemical evidence of Cushing disease (CD) is reported. A magnetic resonance image obtained preoperatively revealed asymmetrical inhomogeneity of the pituitary gland, which was suggestive of localized adenoma. It also showed what was thought to be a small sphenoid polyp. Postoperatively the latter lesion was found to be an ectopic corticotroph adenoma. The pituitary gland, which was free from any tumor, exhibited diffuse unilateral corticotroph hyperplasia. Clinical, radiological, laboratory, and histopathological findings are presented. A review of the literature and a discussion of possible causes of this unique association between the ectopic corticotroph adenoma and the pituitary hyperplasia are provided.
Broadening the clinical spectrum: unusual presentation of spontaneous cerebrospinal fluid hypovolemia
Authors: Nowak Dennis A. , Rodiek Sven-Olaf , Zinner Jürgen , Guhlmann Albrecht , Topka Helge 
Published: May 2009

✓ The syndrome of spontaneous intracranial hypotension is characterized by orthostatic headaches in conjunction with reduced cerebrospinal fluid (CSF) pressure or CSF volume, and characteristic magnetic resonance (MR) imaging findings.
A 50-year-old man presented with a 1-year history of paroxysmal ataxia of gait and short attacks of blurred vision when he stood up from a recumbent position and began to walk. Orthostatic headache was not a feature of his clinical presentation. Magnetic resonance images of the brain revealed diffuse enhancement of the dura mater and hygromas over both cerebral convexities. Magnetic resonance images of the spine demonstrated dilated cervical epidural veins and dilation of the perimedullary veins. Radionuclide cisternography identified a CSF leakage that was localized to the T12—L1 level on subsequent myelograms and on computerized tomography scans obtained after the myelograms. An epidural blood patch was administered and visualized with tungsten powder. The patient's clinical symptoms and sites of disease on imaging completely resolved.
The unusual clinical presentation in this case—paroxysmal ataxia of gait, lack of orthostatic headaches, and dilated epidural and perimedullary venous plexus—supports a recently noted broadening of both the clinical and imaging characteristics of spontaneous intracranial hypovolemia.
Frameless image-guided stereotactic biopsy of parasellar lesions
Authors: Frighetto Leonardo , De Salles Antonio A. F. , Behnke Eric , Smith Zachary A. , Chute Dennis 
Published: May 2009

✓ Interactive image-guided neuronavigation was used to obtain biopsy specimens of cavernous sinus (CS) tumors via the foramen ovale. In this study the authors demonstrated a minimally invasive approach in the management of these lesions.
In four patients, whose ages ranged from 29 to 89 years (mean 61.2 years) and who harbored undefined lesions invading the CS, neuronavigation was used to perform frameless stereotactic fine-needle biopsy sampling through the foramen ovale. The biopsy site was confirmed on postoperative computerized tomography scanning.
The frameless technique was accurate in displaying a real-time trajectory of the biopsy needle throughout the procedure. The lesions within the CS were approached precisely and safely. Diagnostic tissue was obtained in all cases and treatment was administered with the aid of stereotactic radiosurgery or fractionated stereotactic radiotherapy. The patients were discharged after an overnight stay with no complications.
Neuronavigation is a precise and useful tool for image-guided biopsy sampling of CS tumors via the foramen ovale.
Surgical outcomes of 654 ulnar nerve lesions
Authors: Kim Daniel H. , Han Kisoo , Tiel Robert L. , Murovic Judith A. , Kline David G. 
Published: May 2009

Object. In this article the authors present a retrospective analysis of 654 surgical outcomes in patients with ulnar nerve entrapments, injuries, and tumors during a 30-year period.
Methods. Data were gathered between 1968 and 1998 at Louisiana State University Health Sciences Center. Mechanisms of injuries or lesions included 460 entrapments at the elbow level (70%), 76 lacerations (12%), 52 stretches/contusions (8%), 34 fractures/dislocations (5%), 12 gunshot wounds (2%), two injection-induced injuries (0.3%), and 13 nerve sheath tumors (2%).
In cases of entrapment, direct operative recordings uniformly demonstrated a slowing of conduction at the elbow, even in cases in which preoperative noninvasive studies had been nondiagnostic. Intraoperative electrical “inching” studies also demonstrated significant conduction abnormalities that lie just proximal to and through the olecranon notch rather than distal, beneath the flexor carpi ulnaris muscle. There were only eight exceptions to this. Lesions not in continuity due to the injury required primary or secondary end-to-end sutures or graft repair. Aided by intraoperative nerve action potential recording, lesions in continuity received either external or internal neurolysis and split repair or resection followed by end-to-end suture or graft repair. Functional recoveries of Grade 3 or better were seen in 81 (92%) of 88 patients who underwent neurolysis, 42 (72%) of 58 patients who received suture repair, and 24 (67%) of 36 patients who received graft repair. Nevertheless, fewer Grade 4 or 5 recoveries were reached than those seen in patients with radial or median nerve injuries. Nerve sheath tumors were resected with preservation of preoperative function in five of seven patients.
Conclusions. Although difficult to obtain, useful functional recovery can be achieved with proper surgical management of ulnar nerve entrapments and injuries.
Complications of invasive subdural grid monitoring in children with epilepsy
Authors: Önal Çagatay , Otsubo Hiroshi , Araki Takashi , Chitoku Shiro , Ochi Ayako , Weiss Shelly , Logan William , Elliott Irene , Snead O. Carter , Rutka James T. 
Published: May 2009

Object. This study was performed to evaluate the complications of invasive subdural grid monitoring during epilepsy surgery in children.
Methods. The authors retrospectively reviewed the records of 35 consecutive children with intractable localization-related epilepsy who underwent invasive video electroencephalography (EEG) with subdural grid electrodes at The Hospital for Sick Children between 1996 and 2001. After subdural grid monitoring and identification of the epileptic regions, cortical excisions and/or multiple subpial transections (MSTs) were performed. Complications after these procedures were then categorized as either surgical or neurological.
There were 17 male and 18 female patients whose mean age was 11.7 years. The duration of epilepsy before surgery ranged from 2 to 17 years (mean 8.3 years). Fifteen children (43%) had previously undergone surgical procedures for epilepsy. The number of electrodes on the grids ranged from 40 to 117 (mean 95). During invasive video EEG, cerebrospinal fluid leaks occurred in seven patients. Also, cerebral edema (five patients), subdural hematoma (five patients), and intracerebral hematoma (three patients) were observed on postprocedural imaging studies but did not require surgical intervention. Hypertrophic scars on the scalp were observed in nine patients. There were three infections, including one case of osteomyelitis and two superficial wound infections. Blood loss and the amounts of subsequent transfusions correlated directly with the size and number of electrodes on the grids (p < 0.001). Twenty-eight children derived significant benefit from cortical resections and MSTs, with a more than 50% reduction of seizures and a mean follow-up period of 30 months.
Conclusions. The results of this study indicate that carefully selected pediatric patients with intractable epilepsy can benefit from subdural invasive monitoring procedures that entail definite but acceptable risks.
Pseudotumor cerebri syndrome: venous sinus obstruction and its treatment with stent placement
Authors: Owler Brian K. , Parker Geoffrey , Halmagyi G. Michael , Dunne Victoria G. , Grinnell Verity , McDowell David , Besser Michael 
Published: May 2009

Object. Pseudotumor cerebri, or benign intracranial hypertension, is a condition of raised intracranial pressure in the absence of a mass lesion or cerebral edema. It is characterized by headache and visual deterioration that may culminate in blindness. Pseudotumor cerebri is caused by venous sinus obstruction in an unknown percentage of cases. The purpose of this study was to investigate the role of cerebral venous sinus disease in pseudotumor cerebri and the potential of endoluminal venous sinus stent placement as a new treatment.
Methods. Nine consecutive patients in whom diagnoses of pseudotumor cerebri had been made underwent examination with direct retrograde cerebral venography (DRCV) and manometry to characterize the morphological features and venous pressures in their cerebral venous sinuses. The cerebrospinal fluid (CSF) pressure was measured simultaneously in two patients. If patients had an amenable lesion they were treated using an endoluminal venous sinus stent. Five patients demonstrated morphological obstruction of the venous transverse sinuses (TSs). All lesions were associated with a distinct pressure gradient and raised proximal venous sinus pressures. Four patients underwent stent insertion in the venous sinuses and reported that their headaches improved immediately after the procedure and remained so at 6 months. Vision was improved in three patients, whereas it remained poor in one despite normalized CSF pressures.
Conclusions. Patients with pseudotumor cerebri should be evaluated with DRCV and manometry because venous TS obstruction is probably more common than is currently appreciated. In patients with a lesion of the venous sinuses, treatment with an endoluminal venous sinus stent is a viable alternative for amenable lesions.
Polysialylated neural cell adhesion molecules expressed in human pituitary tumors and related to extrasellar invasion
Authors: Trouillas Jacqueline , Daniel Laurent , Guigard Marie-Paule , Tong Soutsakhone , Gouvernet Joanny , Jouanneau Emmanuel , Jan Michel , Perrin Gilles , Fischer Georges , Tabarin Antoine , Rougon Geneviève , Figarella-Branger Dominique 
Published: May 2009

Object. Pituitary adenomas are usually benign tumors; however, some behave aggressively and metastasize. Until now, no specific marker of aggressive behavior or malignancy has been found. The polysialylated neural cell adhesion molecule (NCAM), which is highly expressed in embryonic tissues such as the brain and pituitary, is detected in some neuronal and neuroendocrine tumors. Because polysialylation has been implicated in the regulation of cell growth and migration, polysialylated NCAM expression has been considered as a prognostic marker in such tumors.
Methods. In the present study, the authors analyzed polysialylated NCAM expression in 82 pituitary tumors from humans: 49 secreting adenomas, 32 nonfunctioning adenomas, and one growth hormone and prolactin—secreting carcinoma associated with acromegaly and spinal and liver metastases. Based on immunohistochemical analyses, the tumors were classified as somatotropic (22 tumors), prolactinoma (14 tumors), corticotropic (17 tumors), and gonadotropic or so-called null cell adenomas (28 tumors). Assessment of polysialylated NCAM was performed using three different methods (immunohistochemical analysis, Western blot analysis, and enzyme-linked immunosorbent assay) with a specific mouse monoclonal immunoglobulin M (Men B) that recognizes polysialic acid on NCAM. Tumoral NCAM expression was also evaluated with the aid of immunohistochemical analysis. Using this method, NCAM and polysialylated NCAM were studied in six healthy pituitaries. In addition, corrrelations were investigated using three statistical methods (chi-square test, nonparametric Mann—Whitney U-test, and principal component analysis) to compare tumoral polysialylated NCAM expression and seven parameters (tumor size and type, intrasphenoidal or cavernous sinus invasion, Ki-67 index, mitoses, and patient age and sex).
Neural cell adhesion molecules were expressed in the healthy anterior pituitary and in all tumors. In contrast, polysialylated NCAM was not found in the healthy pituitary gland, but was expressed in 46.3% of typical pituitary tumors and in 85% of the tumors selected as highly aggressive, including one carcinoma and three tumors with histological characteristics that raised suspicion of malignancy. There was no significant correlation between polysialylated NCAM expression and tumor size, tumor type, Ki-67 index, mitoses, or patient age and sex. In contrast, the expression of polysialylated NCAM, which was sensitive to endoneuraminidase-N treatment, was strongly correlated with tumor invasion (p < 0.0001).
Conclusions. In pituitary tumors in humans, expression of polysialylated NCAM is strongly related to tumor invasion and confirms the clinical diagnosis of aggressiveness.
A syndrome of spontaneous cerebral and cervical artery dissections with angiolipomatosis
Authors: Schievink Wouter I. , Thompson Reid C. , Yong William H. 
Published: May 2009

✓ A primary or systemic arteriopathy is frequently suspected in patients with spontaneous cerebral or cervical artery dissections. The authors report on two patients with such dissections accompanied by angiolipomatosis, a previously unreported association, and propose a common developmental defect in these patients.
A 50-year-old man with subcutaneous angiolipomatosis developed painful monocular blindness. Angiography studies revealed a spontaneous extracranial internal carotid artery (ICA) dissection and an ipsilateral fusiform intracranial ICA aneurysm. The ICA dissection was treated with aspirin, and after 6 months a craniotomy was performed. The aneurysm was found to be fusiform; it involved the entire supraclinoid portion of the ICA, and was wrapped with cotton. A 49-year-old man with a congenitally bicuspid aortic valve and subcutaneous angiolipomatosis developed posterior neck pain. Magnetic resonance imaging and angiography demonstrated a fusiform distal vertebral artery aneurysm. A craniotomy was performed and the aneurysm was found to incorporate the posterior inferior cerebellar artery as well as a perforating artery; the lesion was wrapped with cotton.
The tunica media of the arteries of the head and neck as well as the aortic valvular cusps are derived from neural crest cells, and angiolipomatosis has been associated with tumors of neural crest derivation. These associations indicate that a neural crest disorder may be the underlying abnormality in these patients.
Peripheral nerve surgery and neurosurgeons: results of a national survey of practice patterns and attitudes
Authors: Maniker Allen , Passannante Marian 
Published: May 2009

Object. The goal of this study was to determine current practice patterns and attitudes of neurosurgeons toward peripheral nerve surgery.
Methods. A 13-question survey was mailed to all active members of the American Association of Neurological Surgeons and the Congress of Neurological Surgeons. Collected responses were entered into a database and were analyzed using statistical software.
Conclusions. Of 3800 surveys mailed there were 1728 responses for a 45% response rate. Analysis of the data revealed that respondents had a greater comfort level with simple peripheral nerve procedures, such as carpal tunnel release, and a lack of comfort with more complex peripheral nerve procedures, such as brachial plexus exploration. The majority of simple cases were treated by the surveyed neurosurgeons, whereas the majority of complex cases were referred to other surgeons, primarily to other neurosurgeons. The type of medical practice (academic, group, or solo) and the location of the practice (major city, small city, suburban setting, or rural area) showed a statistically significant correlation to simple case referral patterns, whereas the length of time since the respondent underwent training did not. Practice type and location, and years since training showed a statistically significant correlation to complex case referral patterns. Only 48.7% of the respondents believed that they had been given sufficient exposure to peripheral nerve surgery during residency training. The overwhelming majority (97.2%) of respondents favored keeping peripheral nerve surgery as part of the neurosurgical curriculum.
Clinical and neuroimaging characteristics of hydrocephalus associated with vestibular schwannoma
Authors: Tanaka Yuichiro , Kobayashi Shigeaki , Hongo Kazuhiro , Tada Tsuyoshi , Sato Atsushi , Takasuna Hiroshi 
Published: May 2009

Object. The clinical and neuroimaging characteristics of hydrocephalus associated with vestibular schwannoma were retrospectively analyzed to improve the perioperative management of the circulation of cerebrospinal fluid.
Methods. A retrospective analysis was performed in 236 patients with unilateral vestibular schwannomas. The patients' ages ranged from 17 to 83 years (mean 53.6 ± 13.2 years), and the diameters of the tumors the patients harbored ranged from 5 to 60 mm (mean 30.5 ± 12.7 mm). Hydrocephalus was present before tumor resection in 33 patients (14%) and in six of these patients focal dilation of the sylvian fissures was noted. There was a significant correlation between the incidence of hydrocephalus and tumor size. The incidence of preoperative hydrocephalus among elderly patients (≥ 65 years of age) was 28.6% and that among younger patients (< 65 years of age) was 10.8%. Tumors in elderly patients with hydrocephalus (mean tumor diameter 32.8 ±11.7 mm; 12 patients) were significantly smaller than those in younger patients (mean tumor diameter 41.7 ± 10.9 mm; 21 patients). Among patients with tumors smaller than 30 mm (114 patients), the incidence of hydrocephalus in elderly patients (25%) was 12-fold higher than that in younger patients (2.1%). Six patients with hydrocephalus who had focal dilation of the sylvian fissures were significantly older than 27 patients with hydrocephalus in whom there was no focal dilation. The dilated sylvian fissures collapsed in two patients spontaneously after tumor resection and in the other four patients after shunt placement.
Conclusions. The incidence of associated hydrocephalus is higher in older patients. Communicating hydrocephalus tends to occur in elderly patients. Enlargement of the ventricles with focal dilation of the sylvian fissures should not be misinterpreted as physiological brain atrophy.