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Background: Optimal antiplatelet inhibition is essential in patients undergoing neurointerventional procedures; however, variability in response to clopidogrel can contribute to thromboembolic and hemorrhagic complications. The present study evaluated the influence of diabetes mellitus and cigarette smoking on clopidogrel reactivity.Methods: Between 2011 and 2013, 71 consecutive patients underwent aneurysmal coil embolization (CE) or carotid artery stenting (CAS) and received clopidogrel (75 mg daily) and aspirin (100 mg daily) before the treatment. The patients were divided into 2 groups: CE (n = 31) and CAS (n = 40). The patients underwent prospective assessment of preoperative platelet function using VerifyNow assay and received adjunctive cilostazol (200 mg daily, triple antiplatelet therapy) in case of clopidogrel hyporesponse. Patients with clopidogrel hyper-response underwent clopidogrel dose reduction (clopidogrel, 12.5-50 mg daily).Results: Clopidogrel resistance was noted in 15 patients (37.5%) in the CAS group and in 4 patients (12.9%) in the CE group (P = .031). Clopidogrel hyper-response was noted in 2 patients (5%) in the CAS group and in 11 patients (54.8%) in the CE group (P < .001). There was a significant difference in the baseline clinical characteristics between the 2 groups. In the multivariate logistic regression analysis, diabetes and age were independent predictors of clopidogrel hyporesponse, whereas current smoker was an independent predictor of clopidogrel hyper-response.Conclusions: Significant differences in baseline clinical characteristics were present when comparing patients undergoing endovascular treatment of unruptured cerebral aneurysms and carotid artery stenosis. Diabetes mellitus and current smoker status were independent factors related to reactivity to clopidogrel. [ABSTRACT FROM AUTHOR]

Background: Cerebral venous ischemia (CVI) is a rare but potentially significant complication of neurosurgical procedures. However, it is still unclear how cerebral venous occlusion (VO) affects regional cerebral blood flow (rCBF) dynamics. To elucidate its pathophysiology in detail, we examined the real-time perfusion dynamics during adjacent vein occlusions using laser speckle contrast imaging (LSCI) in a rat 2-vein occlusion model.Methods: Two cortical veins were occluded photochemically using rose Bengal dye in 6 male Wistar rats; rCBF was measured in real time with an LSCI before and after VO. Regions of interest were defined between the 2 veins (A) and on the opposite side of the first occluded vein (B) on semi-quantitative pseudocolor images for off-line analysis. Histopathologic evaluation was performed 3 days after the procedure to assess the extent of infarction.Results: LSCI revealed a stepwise reduction in CBF, with a sudden decrease just after the first vein occlusion (~20%) and a further decrease after the second (~30%). Significant differences were observed between rCBF dynamics within regions of interest A and B (P = .0004). All rats exhibited infarcts in the superficial cerebral cortex histopathologically.Conclusions: This is the first report of LSCI specifically applied to the study of CVI. The extensive real-time measurement with high temporal and spatial resolution revealed the stepwise reduction in rCBF during sequential VO and the ensuing infarcts. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a highly aggressive brain tumor for which novel therapeutic approaches, such as immunotherapy, are urgently needed. Zoledronate (ZOL), an inhibitor of osteoclastic activity, is known to stimulate peripheral blood-derived γδT cells and sensitize tumors to γδT cell-mediated killing. To investigate the feasibility of γδT cell-based immunotherapy for patients with GBM, we focused on the killing of GBM cell lines by γδT cells and the molecular mechanisms involved in these cell-cell interactions. Peripheral blood mononuclear cells were expanded in ZOL and interleukin (IL)-2 for 14 days, and γδT cells were enriched in the expanded cells by the immunomagnetic depletion of αβT cells. Gliomas are resistant to NK cells but susceptible to lymphokine-activated killer cells and some cytotoxic T lymphocytes. When the γδT cell-mediated killing of three GBM cell lines (U87MG, U138MG and A172 cells) and an NK-sensitive leukemia cell line (K562 cells) were tested, 32 % U87MG, 15 % U138MG, 1 % A172, and 50 % K562 cells were killed at an effector:target ratio of 5:1. The γδT cell-mediated killing of all three GBM cell lines was significantly enhanced by ZOL and this ZOL-enhanced killing was blocked by an anti-T cell receptor (TcR) antibody. These results indicated that TcR γδ is crucial for the recognition of ZOL-treated GBM cells by γδT cells. Since the low level killing of GBM cells by the γδT cells was enhanced by ZOL, γδT cell-targeting therapy in combination with ZOL treatment could be effective for patients with GBM. [ABSTRACT FROM AUTHOR]

Background: Hyponatremia is a common complication occurring in one third of patients after subarachnoid hemorrhage (SAH). One mechanism that likely mediates the development of hyponatremia in SAH is cerebral salt wasting syndrome (CSWS), which induces natriuresis and reduces total blood volume, resulting in a risk of symptomatic vasospasm (SVS). The mineral corticoid fludrocortisone acetate enhances sodium reabsorption in the renal distal tubules and may help prevent post-SAH hyponatremia. However, management with fludrocortisone acetate is ineffective if hyponatremia is advanced, because CSWS and subsequent SVS develop rapidly. Therefore, an additional earlier marker is required to predict the development of hyponatremia for the initiation of immediate treatment in select patients. However, no conclusive evidence exists showing that hyponatremia influences the risk of SVS, and no standard treatment protocol exists for treating hyponatremia in patients with SAH. This study was undertaken to evaluate whether selective early treatment of hyponatremia prevents SVS in patients with increased urinary sodium excretion in the early phase following SAH. Methods: A total of 103 patients with aneurysmal SAH were managed for a postoperative electrolyte disorder after aneurysmal clipping or coil embolization. Between 2004 and 2007 (period 1), 54 patients started treatment to correct the electrolyte disorder after hyponatremia had occurred. Between 2007 and 2011 (period 2), 49 patients were prospectively subjected to sodium replacement treatment according to their daily sodium balance, and inhibition of natriuresis with fludrocortisone acetate was initiated just after an increase in urinary sodium excretion >300 mEq/day. The occurrence of hyponatremia, SVS, and outcomes were compared between the two periods. Results: Hyponatremia was observed in 14 patients (26%) in period 1 and 7 patients (14%) in period 2. The incidence of fludrocortisone acetate administration was significantly higher, and initiation of electrolyte correction was significantly earlier, in period 2 patients. We observed a significant difference in the frequency of SVS, which occurred in 10 patients (18.5%) in period 1 and 3 patients (6.1%) in period 2. Both urinary sodium excretion and urine volume at day 7 were significantly different between the two periods. However, no significant difference was observed in overall outcome between the two periods. Conclusions: Early inhibition of natriuresis with fludrocortisone acetate before the occurrence of hyponatremia prevented SVS after aneurysmal SAH. Increased urinary sodium excretion in the early phase of SAH is a good indicator for the initiation of electrolyte correction with fludrocortisone acetate. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: Central nervous system germinomas often extend or disseminate into the ventricular and subarachnoid space. We present a case of primary central nervous system germinoma consisting mainly of meningeal dissemination, which is extremely unusual. Case report: A 16-year-old boy presented with pure germinoma, manifesting as anorexia and headache for 10 days. Radiological examinations revealed a large mass lesion in the posterior fossa and a small mass lesion on the pineal lobule with thickening of the tentorium cerebelli and falx. The patient underwent partial removal of the infratentorial tumor via open surgery. Intraoperative findings indicated extension of the dural and supracerebellar mass lesions into the epiarachnoid space. Three chemotherapy courses comprising ifosfamide, etoposide, and cisplatin were administered after the surgery. Craniospinal irradiation was administered subsequently. The adjuvant therapy had a complete response. Conclusion: Central nervous system germinoma cells may have similar compatibility to meningeal components as they do to cerebrospinal fluid or the ventricular system. If there is a possibility of the tumor extending into the subdural space during surgical intervention or other events, a range of postdiagnostic irradiation should be considered to cover a wider range. [ABSTRACT FROM AUTHOR]

We have developed a prototype full-resolution Super Hi-Vision (SHV) plasma display panel (PDP) that has 4,320 scanning lines and over 33-million pixels. Highly realistic SHV programs were the first successfully reproduced on a 145-inch diagonal PDPs with a 0.417-mm pixel pitch by applying a new panel driving method. [ABSTRACT FROM AUTHOR]

We have been applying a low discharge voltage (Ca, Mg)O protective layer to plasma display panels (PDPs) to reduce their power consumption. However, (Ca, Mg)O is highly reactive with CO2, and the resulting carbonate formation during high-temperature panel sealing in air impairs the low discharge voltage characteristic. We investigated the mechanism of the carbonation reaction that occurs on a (Ca, Mg)O surface during annealing in air at 450°C and found that the CO2 diffuses through the formed CaCO3 layer and that a (Ca, Mg)O + CO2 r̊ CaCO3 + MgO reaction then occurs. This carbonation reaction evidently stops when the growing MgO finally forms a layer at all boundaries between the CaCO3 and (Ca, Mg)O regions. [ABSTRACT FROM AUTHOR]

Purpose: The amount of blood on computed tomography (CT) has been shown to be a predictor of cerebral vasospasm after subarachnoid hemorrhage (SAH). However, the influence of the location of the blood on the incidence of vasospasm remains unclear. We retrospectively assessed the association of the blood volumes in the individual components (cisterns and fissures) of CT scans with angiographic vasospasm after SAH. Methods: One hundred forty-nine SAH patients scheduled for cerebral aneurysm clipping were enrolled. The amount of subarachnoid blood was classified using the Fisher CT grade . The amounts of subarachnoid blood in 5 cisterns or 3 fissures were also evaluated using SAH scores ranging from 0 to 3 (0, no blood; 3, completely filled with blood). Cerebral vasospasm was diagnosed by the results of angiography. Results: Angiographic vasospasm developed in 51 of 149 patients (34%). Of those, 26 patients were symptomatic. The Fisher CT grade and SAH scores in the right and left sylvian fissures and suprasellar cisterns were significantly higher in patients with angiographic vasospasm than in those without it. Univariate logistic regression analysis revealed that a high Fisher CT grade and high SAH scores in the right and left sylvian fissures and suprasellar cisterns were predictors of angiographic vasospasm. Multivariate analysis indicated that the SAH score in the right sylvian fissure was an independent predictor of angiographic vasospasm (odds ratio, 3.6; 95% confidence interval (CI), 1.7-7.7; P = 0.01). Conclusion: The results indicated that the amount of blood in the right sylvian fissure was significantly associated with the development of angiographic vasospasm after SAH. [ABSTRACT FROM AUTHOR]

The sustain pulse voltage of the panel for 66-kPa Ne + Xe (5%-30%) is 20%-40% lower with a Sr0.62Ca0.38O protective layer than with a MgO protective layer. At a normal sustain voltage of 160-200 V, the luminous efficiency of the panel with the Sr0.62Ca0.38O protective layer for Xe (30%) is about twice as high as with the MgO protective layer for Xe (10%). The luminances of these panels are almost the same. This high efficiency at normal sustain pulse voltage and normal luminance is obtained through the combined use of the Sr0.62Ca0.38O protective layer and high Xe content. With regard to ion bombardment, the Sr0.62Ca0.38O film has a 4.5 times longer life than SrO film and nearly 80% of the life of MgO film. We also calculated the values of theoretical secondary electron emission yield γi min of MgO, SrO, and CaO without energy bands in the band gap for rare gas ions and found that [γi min of MgO] ≤ [γi min of CaO] < [γi min of SrO] except for the one case with He. The breakdown voltage decreases with higher γi min values. As expected, the discharge voltage of the panel is much lower with the SrO protective layer than with the MgO protective layer. The discharge voltages of the panels with Sr0.62Ca0.38O and SrO protective layers are almost the same. These findings show that the life of the SrO protective layer can be made 4.5 times longer without any increase in the discharge voltage by adding CaO (40 at.%). [ABSTRACT FROM AUTHOR]

Secondary electron emission yield γ values for rare-gas particles (He, Ne, Ar, Kr, and Xe ions of atoms and molecules, metastable atoms, and excimers) of MgO deposited under optimum conditions for the highest γ values were calculated assuming the Auger transitions between the valence band, and the F (oxygen ion vacancy + two electrons) and F+ (oxygen ion vacancy + one electron) centers in the MgO surface. These calculated γ values are probably the same as γ values for MgO used in practice. As for combination of the MgO with these rare-gas particles, all the calculated γ values fall to nonzero; resonance neutralization cannot occur for the rare-gas particles except Ne and Xe2 ions. Therefore, γ values of the MgO for these rare-gas particles, other than Ne and Xe2 ions, are determined only by Auger neutralization. For Ne and Xe2 ions, the influence of resonance neutralization effect on calculated γ values of ions is small. Therefore, γ values of the MgO for Ne and Xe2 ions are also almost determined only by Auger neutralization. The γ values for the ions of atoms are a little larger than those for the ions of molecules. The γ values of the metastable atoms are also a little larger than those of the excimers. As for MgO without defect states, calculated γ values of Ar, Kr, and Xe ions of atoms and molecules fall to zero; calculated γ value of Xe2 excimer at the lowest continuous spectrum also falls to zero; these calculated γ values for MgO without defect states are probably the lowest values theoretically. As for rare-gas ions of atoms, the calculated γ values have been compared with experimental results reported previously. These results will be useful in detailed investigations into the mechanism of discharge of plasma display panels (PDPs). [ABSTRACT FROM PUBLISHER]

Deals with a study that developed formulas for the calculation of the secondary electron field of an insulator without impurity levels derived from Hagstrum's theory to provide a guideline in the search for optimum cathode materials for plasma display panels. Theoretical background; Methodology of the study; Results and discussion.

Error correction and error detection techniques are often used in wireless transmission systems. The Asynchronous Transfer Mode (ATM) employs Header Error Control (HEC). Since ATM specifications have been developed for high quality optical fiber transmission systems, HEC has single bit error correction and multiple bit error detection capabilities. When HEC detects multiple bit error, the cell is discarded. However, wireless ATM requires a more powerful Forward Error Correction (FEC) scheme to improve the Bit Error Rate (BER) performance resulting in a reduction in the transmission power and antenna size. This concatenation of wireless FEC and HEC of the ATM may effect cell loss performance. This paper proposes error correction and error detection techniques suitable for wireless ATM and analyzes the performance of the proposed schemes. [ABSTRACT FROM AUTHOR]

Although intracranial pressure is considered to be normal in children with autism spectrum disorder (ASD), we aimed to assess whether such children may have increased intracranial pressure using noninvasive computed tomography (CT). Head CT scans of children with ASD (109 cases, male 91 and female 18, average age 4.3 years) and of children with typical development (60 cases, male 35 and female 25, average age 4.5 years) were acquired. The images were processed to map the shape of the inner skull surface. We predicted that a complex skull shape, based on a marked digital impression, would be indicative of chronically increased intracranial pressure. The data of the scans were extracted and processed to automatically establish inner and outer cranial circumferences. The circularity (reflecting inner skull shape and area) and C-ratio (ratio of inner/outer circumference) were determined and statistically analyzed. The circularity and C-ratio were significantly lower in children with ASD than in children with typical development. A lower circularity was associated with a more complex shape of the inner skull surface, which indicated the presence of intracranial hypertension. Our study suggests that children with ASD may be at a risk for chronic intracranial hypertension. Our technique incorporating the circularity and C-ratio is a useful noninvasive method for screening such patients and could impact future investigations of ASD. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM), which is the most common malignant brain tumor, is resistant to standard treatments. Immunotherapy might be a promising alternative for the treatment of this cancer. Chimeric antigen receptor (CAR) is an artificially modified fusion protein that can be engineered to direct the specificity and function of T cells against tumor antigens. However, the antitumor effects of EGFRvIII-targeting CAR-T (EvCAR-T) cells in GBM are limited. The inhibitory effect is induced by the interaction between programmed cell death protein 1 (PD-1) on activated EvCAR-T cells and its ligands on GBM cells. In the present study, PD-1-disrupted EvCAR-T cells were established using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9). The sgRNA/Cas9 expression vectors designed precisely disrupted the target region of PD-1 and inhibited the expression of PD-1 in EvCAR-T cells. The PD-1-disrupted EvCAR-T cells had an in vitro growth inhibitory effect on EGFRvIII-expressing GBM cells without altering the T-cell phenotype and the expression of other checkpoint receptors. In the future, the in vivo antitumor effect of this vector should be evaluated in order to determine if it could be applied clinically for improving the efficacy of EvCAR-T cell-based adoptive immunotherapy for GBM. [ABSTRACT FROM AUTHOR]