The case of a 12-year-old boy with anaplastic astrocytoma of the left thalamus is reported. Postoperative irradiation and chemotherapy could not repress tumor progression; therefore, treatment was undertaken with an oncolytic virus, MTH-68/H, an attenuated strain of Newcastle disease virus (NDV), and valproic acid (VPA), an antiepileptic drug, which also has antineoplastic properties. This treatment resulted in a far-reaching regression of the thalamic glioma, but 4 months later a new tumor manifestation, an extension of the thalamic tumor, appeared in the wall of the IVth ventricle, which required a second neurosurgical intervention.
View Article and Find Full Text PDFBackground: The lack of detailed understanding of the mechanism of action of many biowarfare agents poses an immediate challenge to biodefense efforts. Many potential bioweapons have been shown to affect the cellular pathways controlling apoptosis 1234. For example, pathogen-produced exotoxins such as Staphylococcal Enterotoxin B (SEB) and Anthrax Lethal Factor (LF) have been shown to disrupt the Fas-mediated apoptotic pathway 24.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
February 2006
We investigate a suggested path to self-organized criticality. Originally, this path was devised to "generate criticality" in systems displaying an absorbing-state phase transition, but nothing in its definition forbids the mechanism to be used in any other continuous phase transition. We used the Ising model as well as the Manna model to demonstrate how the finite-size scaling exponents depend on the tuning of driving and dissipation rates with system size.
View Article and Find Full Text PDFBackground: Pontine gliomas are the subgroup of brainstem gliomas with the worst prognosis. Controversial treatment approaches are discussed.
Patients And Methods: Data of children with pontine gliomas treated in different prospective multi-center studies who were registered in the HIT-GBM database were pooled and analyzed addressing prognostic factors and the relevance of intensive treatment using contingency tables, Kaplan-Meier curves and Cox regression analyses.
Aim: To study the effect of different apical shapes in prepared simulated root canals on the application of a commercially prepared calcium hydroxide paste by a syringe or lentulo spiral.
Methodology: Three different types of root canal preparation were performed in 90 simulated canals: group A to an apical size 20 and a 0.10 taper using hand and rotary instruments, group B to an apical size 30 and a 0.
Correlations in the azimuthal angle between the two largest transverse momentum jets have been measured using the D0 detector in p (-)p collisions at a center-of-mass energy sqrt[s]=1.96 TeV. The analysis is based on an inclusive dijet event sample in the central rapidity region corresponding to an integrated luminosity of 150 pb(-1).
View Article and Find Full Text PDFBackground: Preradiation chemotherapy including methotrexate (MTX) was effective in children with completely resected high-grade gliomas (HGG). The specific role of MTX remains uncertain.
Patients And Methods: Children with newly diagnosed HGG and diffuse intrinsic pontine gliomas (DIPG) were enrolled.
Aim: To evaluate the relative performance of Endo-Eze Anatomic Endodontic Technology (AET) stainless steel instruments when shaping maxillary molar root canals in vitro. Methodology Extracted human maxillary molars were scanned, before and after root canal shaping with Endo-Eze AET, employing micro-computed tomography (muCT) at an isotropic resolution of 34 microm. Three-dimensional root canal models were reconstructed and evaluated for volume, surface area, 'thickness' (diameter), canal transportation and prepared surface.
View Article and Find Full Text PDFIn the corpus callosum, astrocytic calcium waves propagate via a mechanism involving ATP-release but not gap junctional coupling. In the present study, we report for the neocortex that calcium wave propagation depends on functional astrocytic gap junctions but is still accompanied by ATP-release. In acute slices obtained from the neocortex of mice deficient for astrocytic expression of connexin43, the calcium wave did not propagate.
View Article and Find Full Text PDFThe ratio of the B+ and B0 meson lifetimes was measured using data collected in 2002-2004 by the D0 experiment in Run II of the Fermilab Tevatron Collider. These mesons were reconstructed in B-->mu(+)nuD(*-)X decays, which are dominated by B0 and B-->mu(+)nuD 0X decays, which are dominated by B+. The ratio of lifetimes is measured to be tau(+)/tau(0)=1.
View Article and Find Full Text PDFUsing the data collected with the D0 detector at square root(s) = 1.96 TeV, for integrated luminosities of about 180 pb(-1), we have measured the ratio of inclusive cross sections for pp --> Z + b jet to pp --> Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider.
View Article and Find Full Text PDFWe present a measurement of the W boson pair-production cross section in pp collisions at a center-of-mass energy of sqrt[s]=1.96 TeV. The data, collected with the Run II D0 detector at Fermilab, correspond to an integrated luminosity of 224-252 pb(-1) depending on the final state (ee, emu, or mumu).
View Article and Find Full Text PDFBackground And Purpose: Spreading depression (SD)-like depolarizations may augment neuronal damage in neurovascular disorders such as stroke and traumatic brain injury. Spreading ischemia (SI), a particularly malignant variant of SD-like depolarization, is characterized by inverse coupling between the spreading depolarization wave and cerebral blood flow. SI has been implicated in particular in the pathophysiology of subarachnoid hemorrhage.
View Article and Find Full Text PDFAstrocytes express a variety of metabotropic receptors and their activation leads to a biphasic Ca2+ response due to Ca2+ release from intracellular stores and subsequent capacitative Ca2+ entry. We performed Ca2+ imaging with Fura-2 on cultured mouse astrocytes and showed that extracellular zinc reversibly blocks the capacitative Ca2+ entry following application of the metabotropic ligands ATP, glutamate and endothelin-1. Zinc blocked the plateau phase of the ligand-triggered Ca2+ responses.
View Article and Find Full Text PDFAim: To evaluate the effects of lubrication on torque generated during rotary preparation of simulated root canals in dentine using ProFile and ProTaper Nickel-Titanium instruments.
Methodology: Thirty-two 3 mm thick dentine discs were used for this study. Four pilot holes were drilled perpendicularly through each disc.
We present a search for Wbb production in pp collisions at sqrt[s]=1.96 TeV in events containing one electron, an imbalance in transverse momentum, and two b-tagged jets. Using 174 pb(-1) of integrated luminosity accumulated by the D0 experiment at the Fermilab Tevatron collider, and the standard-model description of such events, we set a 95% C.
View Article and Find Full Text PDFWe present the results of a search for the flavor-changing neutral current decay B(0)(s)--> mu(+) mu(-) using a data set with integrated luminosity of 240 pb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector in run II of the Fermilab Tevatron collider. We find the upper limit on the branching fraction to be B(B(0)(s)--> mu(+) mu(-)) < or= 5.
View Article and Find Full Text PDFPhys Rev Lett
February 2005
Using the exclusive decay B0s-->J/psi(mu+mu-)phi(K+K-), we report the most precise single measurement of the B0s lifetime. The data sample corresponds to an integrated luminosity of approximately 220 pb(-1) collected with the D0 detector at the Fermilab Tevatron Collider in 2002-2004. We reconstruct 337 signal candidates, from which we extract the B0s lifetime, tau(B0s)=1.
View Article and Find Full Text PDFPhys Rev Lett
February 2005
We report the results of a search for supersymmetry (SUSY) with gauge-mediated breaking in the missing transverse energy distribution of inclusive diphoton events using 263 pb(-1) of data collected by the D0 experiment at the Fermilab Tevatron Collider in 2002-2004. No excess is observed above the background expected from standard model processes, and lower limits on the masses of the lightest neutralino and chargino of about 108 and 195 GeV, respectively, are set at the 95% confidence level. These are the most stringent limits to date for models with gauge-mediated SUSY breaking with a short-lived neutralino as the next-to-lightest SUSY particle.
View Article and Find Full Text PDFWe present measurements of the Lambda(0)(b) lifetime in the exclusive decay channel Lambda(0)(b)--> J/psiLambda(0), with J/psi--> mu(+)mu(-) and Lambda(0)--> ppi(-), the B0 lifetime in the decay B0-->J/psiK(0)(S) with J/psi--> mu(+)mu(-) and K(0)(S)-->pi(+)pi(-), and the ratio of these lifetimes. The analysis is based on approximately 250 pb(-1) of data recorded with the D0 detector in pp collisions at sqrt[s] = 1.96 TeV.
View Article and Find Full Text PDFThe aim of the present study was to evaluate static fracture loads of ProTaper Nickel-Titanium instruments that had been subjected to various degrees of cyclic fatigue. Torque and angle at failure of new instruments and instruments that had been stressed to 30, 60, or 90% of their cyclic fatigue rotations in a simulated canal (90 degrees and 5 mm radius) were tested according to ISO 3630-1. With unused ProTaper instruments, resistance to cyclic fatigue decreased with diameter increase and ranged from 158 to 450 rotations.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
December 2004
Self-organized criticality can be translated into the language of absorbing state phase transitions. Most models for which this analogy is established have been investigated for their absorbing state characteristics. In this paper, we transform the self-organized critical Oslo model into an absorbing state Oslo model and analyze the avalanche behavior.
View Article and Find Full Text PDFThe aim of this study was to compare torques and forces developed by two sequences of nickel-titanium rotary instruments, using only .04 taper instruments or a combination of .04 and .
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