J/ψ suppression at forward rapidity in Pb-Pb collisions at √s(NN) = 2.76 TeV

The ALICE experiment has measured the inclusive J/ψ production in Pb-Pb collisions at √s(NN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/ψ yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545 ± 0.032(stat) ± 0.083(syst) and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/ψ production from charm quarks in a deconfined partonic phase can describe our data.

J/ψ polarization in pp collisions at √s=7 TeV

The ALICE Collaboration has studied J/ψ production in pp collisions at √s=7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/ψ polarization parameters λ(θ) and λ(φ) were obtained. The study was performed in the kinematic region 2.5<y<4, 2<p(t)<8 GeV/c, in the helicity and Collins-Soper reference frames. In both frames, the polarization parameters are compatible with zero, within uncertainties.

Adenoma malignum of the uterine cervix: ultrasonographic findings in 11 patients

OBJECTIVE

To evaluate the ultrasonographic features of adenoma malignum, a minimal deviation adenocarcinoma of the uterine cervix.

METHODS

Eighteen consecutive patients with pathologically confirmed adenoma malignum were enrolled in this study at two institutions. Preoperative ultrasound examination was performed and the results were available in 11 patients. We analyzed retrospectively the gray-scale ultrasound findings for the following morphologic characteristics: cervical enlargement, as well as size, location and ultrasonographic characteristics of lesions. In five patients we also evaluated Doppler features with regard to intralesional vascularity.

RESULTS

The cervix was enlarged in 73% (8/11) of cases. The mean greatest tumor diameter was 4.2 (range, 2.5-6.8) cm. In five (45%) cases, the cervix was completely infiltrated by the tumor. At gray-scale ultrasound examination, three (27%) tumors were multilocular lesions, four (36%) were multilocular lesions with solid components and four (36%) were solid lesions. In the multilocular lesions with or without a solid component, locules tended to be 1 cm or less in average diameter (86%, 6/7 cases) and there tended to be 11-20 in number (57%, 4/7 cases). In most (57%, 4/7) cases the locular fluid was homogeneously hypoechoic. Most (75%, 3/4) solid lesions manifested heterogeneous echogenicity. The five (100%) tumors examined with Doppler manifested moderate or abundant color content on color or power Doppler.

CONCLUSIONS

Adenoma malignum can appear sonographically as solid, multilocular and multilocular solid cervical lesions. Awareness of its clinical and ultrasonographic features might improve diagnosis before surgery.

Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at sqrt(s(NN)) = 2.76  TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

Midrapidity antiproton-to-proton ratio in pp collisons at sqrt[s]=0.9 and 7 TeV measured by the ALICE experiment

The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at sqrt[s]=0.9 and 7 TeV during the initial running periods of the Large Hadron Collider. The measurement covers the transverse momentum interval 0.45<p_{t}<1.05  GeV/c and rapidity |y|<0.5. The ratio is measured to be R_{|y|<0.5}=0.957±0.006(stat)±0.014(syst) at 0.9 TeV and R_{|y|<0.5}=0.991±0.005(stat)±0.014(syst) at 7 TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

Registration of sheep brain MR images for cell tracking using ferrite-composite micro-beads as markers

In the recent molecular imaging studies of the magnetic resonance imaging field, in-vivo cell tracking is becoming an issue for the observation of cell therapy and disease behavior. In order to perform cell tracking, high resolution images and long-term studies are required, because those images make better performance than low resolution images in the recognition of cells and cells are traced at least two weeks. Image registration is an essential image processing technique for long-term imaging. In this study, we proposed the image registration technique using ferrite-composite micro- beads which could be used as substitutes for the cells labeling MR contrast agent such as superparamagnetic iron oxide (SPIO) nanoparticles. Registration of sheep brain images tagging micro-beads was performed with the sufficient accuracy for cell tracking.

Comparison of birdcage and phase array coil using FDTD for the B(1) homogeneity in high field MRI

RF coils play an important role to acquire MR images with the maintenance of high homogeneity in high field MR system more than 3.0 T. Many kinds of RF coils such as birdcage coil, STR, surface coil, and phase array coil have been used, however, the good uniformity of a coil has always been an issue. In this paper, comparison of B(1) homogeneity between birdcage and phase array coil was investigated using FDTD method at 3.0 T MRI in order to develop RF coils with the high uniformity. Three different configurations of the FDTD simulation were performed like as using a free space configuration, water phantom configuration, and head mesh model. B1 homogeneity was calculated to the case of birdcage coil and 8-channel phase array coil in each configuration of simulation. Improvement on the homogeneity of the images and reduction of standing wave effect was achieved with comparing the real MR images with the result from simulation.

Cerebral lipiodol embolism during transcatheter arterial chemoembolization

Cerebral lipiodol embolism (CLE) is a rare complication that may occur during chemoembolization. The authors present three cases of CLE during transcatheter arterial chemoembolization for hepatocellular carcinoma. Multiple small nonconfluent hyperintense intracerebral lesions were found on the diffusion-weighted and fluid-attenuated inversion recovery MRI. Clinical signs completely resolved and MRI lesions markedly improved on follow-up evaluation within a 3-week period.

Some technical aspects of magnetic stimulation coil design with the ferromagnetic effect

The performance of the stimulation coil in a magnetic nerve stimulator can be improved by attaching a ferromagnetic structure to the coil. This reduces heat generation at the coil and increases magnetic field strength for a given unit of current. Some technical aspects of the design of a stimulation coil with a ferromagnetic structure have been studied. Finite element method analysis results are presented for the effect of size, depth and magnetic saturation of the ferromagnetic structure on the stimulation coil performance. The experimental results show that the stimulation coil performance is improved by up to 40% by the attaching of a ferromagnetic structure on the coil.

Reperfusion differentially induces caspase-3 activation in ischemic core and penumbra after stroke in immature brain

BACKGROUND AND PURPOSE

Different strategies for neuroprotection of neonatal stroke may be required because the developing brain responds differently to hypoxia-ischemia than the mature brain. This study was designed to determine the role of caspase-dependent injury in the pathophysiology of pure focal cerebral ischemia in the immature brain.

METHODS

Postnatal day 7 rats were subjected to permanent or transient middle cerebral artery (MCA) occlusion. Diffusion-weighted MRI was used during occlusion to noninvasively map the evolving ischemic core. The time course of caspase-3 activation in ischemic brain tissue was determined with the use of an Asp-Glu-Val-Asp-aminomethylcoumarin cleavage assay. The anatomy of caspase-3 activation in the ischemic core and penumbra was mapped immunohistochemically with an anti-activated caspase-3 antibody in coronal sections that matched the imaging planes on diffusion-weighted MRI.

RESULTS

A marked increase in caspase-3 activity occurred within 24 hours of reperfusion after transient MCA occlusion. In contrast, caspase-3 activity remained significantly lower within 24 hours of permanent MCA occlusion. Cells with activated caspase-3 were prominent in the penumbra beginning at 3 hours after reperfusion, while a more delayed but marked caspase-3 activation was observed in the ischemic core by 24 hours after reperfusion.

CONCLUSIONS

In the neonate, caspase-3 activation is likely to contribute substantially to cell death not only in the penumbra but also in the core after ischemia with reperfusion. Furthermore, persistent perfusion deficits result in less caspase-3 activation and appear to favor caspase-independent injury.

Dosimetric and radiographic correlates to prostate brachytherapy-related rectal complications

Despite rates of radiation proctitis reported in the 1% to 9% range in most series, there is little information regarding rectal morbidity and dosimetric parameters. Accordingly, we have analyzed computed tomography (CT)-based dosimetric parameters based on a series of patients with endoscopically proven radiation proctitis. Nine patients diagnosed with radiation proctitis on endoscopy were identified in a prior review of 160 consecutively treated patients at the University of Washington in 1997. For each proctitis patient, two patients with no rectal bleeding matched for prostate size, isotope, and dose were selected as controls. Axial CT images obtained 2 to 4 hour postoperatively were used for postimplant dosimetry. Dose volume histograms of the rectum, surface area of the outer rectal wall receiving > or = 100% of the prescribed dose, maximum rectal dose, and length of rectum receiving > or = 100% prescription were obtained. Preimplant CT scans were used to group patients into three categories based on the amount of apparent rectal contact with the prostate. All rectal dosimetric parameters were statistically different between patients with or without rectal bleeding. The mean surface area receiving at least 100% prescription dose was 3.1 cm(2) for the controls vs. 6.9 cm(2) for the rectal bleeders (P = 0.001). The volume of rectum receiving at least 100% of prescription dose was 0.6 cc for the controls vs. 2.5 cc for the bleeders (P = 0.00008). Patients with full prostate-rectal contact had significantly higher rectal dose parameters compared to those with partial or no rectal contact. All nine proctitis patients were in the full-rectal-contact group compared to only seven of 18 (39%) controls. This detailed dosimetric analysis shows higher rectal doses for patients with radiation proctitis, making it a potential method of identifying patients at higher risk for receiving excessive rectal doses based on the anatomic relationship between the rectum and prostate on CT scan. Published 2001 Wiley-Liss, Inc.

BAX contributes to apoptotic-like death following neonatal hypoxia-ischemia: evidence for distinct apoptosis pathways

BACKGROUND

Hypoxic-ischemic (H-I) injury to the neonatal brain has been shown to result in rapid cell death with features of acute excitotoxicity/necrosis as well as prominent delayed cell death with features of apoptosis such as marked caspase-3 activation. BAX, a pro-apoptotic molecule, has been shown to be required for apoptotic neuronal cell death during normal development but the contribution of endogenous BAX in cell death pathways following H-I injury to the developing or adult brain has not been studied.

MATERIALS AND METHODS

Bax +/+, +/-, and -/- mice at post-natal day 7 were subjected to unilateral carotid ligation followed by exposure to 45 minutes of 8% oxygen. At different timepoints following H-I, brain tissue was studied by conventional histology, immunohistochemistry, immunofluorescence, Western blotting, and enzymatic assay to determine the extent and type of cell injury as well as the amount of caspase activation.

RESULTS

We found that bax -/- mice had significantly less (38%) hippocampal tissue loss than mice expressing bax. Some of the remaining cell death in bax -/- mice, however, still had features of apoptosis including evidence of nuclear shrinkage and caspase-3 activation. Though bax -/- mice had significantly decreased caspase-3 activation as compared to bax expressing mice following H-I, the density of cells with activated caspase-8 in the CA3 region of the hippocampus did not differ between bax +/- and bax -/- mice.

CONCLUSIONS

These findings demonstrate that endogenous BAX plays a role in regulating cell death in the central nervous system (CNS) following neonatal H-I, a model of cerebral palsy. In addition, while BAX appears to modulate the caspase-3 activation following neonatal H-I, caspase-8 which is linked to death receptor activation, may contribute to apoptotic-like neuronal death in a BAX-independent manner.

Patient reported complications after prostate brachytherapy

PURPOSE

Prostate brachytherapy has gained popularity due partly to the low rates of short-term complications shown in studies from highly select clinical practices. These series rely on medical records generated by the treating physician and are prone to underreport complications. We summarize the complication reports obtained directly from patients to establish a more realistic incidence of treatment related problems.

MATERIALS AND METHODS

In 1997, 160 consecutive patients treated with prostate brachytherapy at the University of Washington were studied. A questionnaire was designed to determine the rate of complications occurring within 1 year of the procedure. The questions were formulated for ease of use and conciseness, while accounting for easily recalled events associated with complications. A total of 147 (92%) patients completed the questionnaire.

RESULTS

There were 8 (5%) patients who required hospital admission for an average of 2 days (range 1 to 7) as a result of the procedure. A total of 56 (38%) patients required nonroutine visits with a physician in an office setting or at an emergency room. Radiation proctitis diagnosed by endoscopy developed in 8 (5%) patients but no one needed surgical intervention. A total of 47 (32%) patients required urinary catheterization at some point after implantation.

CONCLUSIONS

We demonstrated a higher rate of short-term complications than those previously reported. Fortunately, the majority of side effects were self-limited and no treatment related mortality or cardiovascular morbidity was seen. Our findings may provide a more realistic account of the complications likely to occur after implantation than might be surmised from previous reports.

Antimetastatic and antitumor effects of benzoquinonoid AC7-1 from Ardisia crispa

An antimetastatic and cytostatic substance, termed AC7-1, was isolated from Ardisia crispa and identified as a benzoquinonoid compound, 2-methoxy-6-tridecyl-1,4-benzoquinone. It was originally characterized as the potent PAF (platelet-activating factor) receptor-binding antagonist with nonspecific antiplatelet effects on platelet aggregation induced by various agonists including PAF, ADP, thrombin and collagen. The nonspecific antiaggregatory properties of AC7-1 drew our interest given its possible relationship in integrin receptor-binding antagonistic activity. The integrin receptor plays an important role in metastasis and thrombosis as the cell surface transmembrane protein. Based on the aforementioned facts, the antimetastatic activities of AC7-1 were examined using various in vitro and in vivo metastasis assays. AC7-1 strongly blocked B16-F10 melanoma cell adhesion to extracellular matrix (ECM) and B16-F10 melanoma cell invasion. AC7-1 also remarkably inhibited pulmonary metastasis and tumor growth in vivo. AC7-1 inhibited B16-F10 melanoma cell adhesion to only specific synthetic peptides including RGDS. These findings suggest that antimetastatic activities of AC7-1 can be caused by blocking integrin-mediated adherence. We found AC7-1 to be a potential candidate for the development of a new antimetastatic drug.

Inhibition of calmodulin-dependent calcium-ATPase and phosphodiesterase by various cyclopeptides and peptide alkaloids from the Zizyphus species

The effects of various sedative cyclopeptides and peptide alkaloids from the Zizyphus species on calmodulin-dependent Ca2+-ATPase and phosphodiesterase were investigated. Calmodulin-induced activation of Ca2+-ATPase was strongly inhibited by sanjoinine-A dialdehyde (IC0O, 2.3 microM), -Ah1 (IC50, 4.0 microM), -A (IC50, 4.6 microM), and -G2 (IC50, 7.2 microM), while calmodulin-induced activation of phosphodiesterase was strongly inhibited by both deachuine-S10 (IC30, 4.9 microM) and sanjoinine-D (IC50, 9.0 microM). The inhibitory activity of the various cyclopeptides and peptide alkaloids on Ca2+-ATPase was found to correlate well with their sedative activity.

In vitro inhibitory effect of protopanaxadiol ginsenosides on tumor necrosis factor (TNF)-alpha production and its modulation by known TNF-alpha antagonists

Ginsenosides are the major principles of Panax ginseng C. A. Meyer (Araliaceae) used as a mild oriental folk medicine. In this report, we have examined the inhibitory potency of protopanaxadiol ginsenosides (PPDGs) such as Rb1, Rb2 and Rc, and their co-treatment effect with known tumor necrosis factor (TNF)-alpha antagonists on TNF-alpha production in either murine (RAW264.7) or human (U937) macrophages stimulated with lipopolysaccharide (LPS). Rb1, and Rb2 strongly suppressed TNF-alpha production in RAW264.7 cells with an IC50 of 56.5 and 27.5 microM, respectively, and in differentiated U937 cells with an IC50 of 51.3, and 26.8 microM, respectively. The inhibitory activity of Rb1 and Rb2 was significantly increased by pharmacological agents against protein kinase C, protein tyrosine kinase, and protein kinase A, and anti-rheumatoid arthritis drugs, such as chloroquine and steroid drugs. In contrast, only cyclic AMP phosphodiesterase (cAMP PDE) inhibitors among cAMP-elevating agents did not change the inhibitory potency of PPDGs. These data suggest that PPDGs may possess potential therapeutic efficacy against TNF-alpha mediated disease and the therapeutic potency of PPDGs may be enhanced when co-treated with various kinds of known TNF-alpha antagonists but not with cAMP PDE inhibitors.

Clusterin contributes to caspase-3-independent brain injury following neonatal hypoxia-ischemia

Clusterin, also known as apolipoprotein J, is a ubiquitously expressed molecule thought to influence a variety of processes including cell death. In the brain, it accumulates in dying neurons following seizures and hypoxic-ischemic (H-I) injury. Despite this, in vivo evidence that clusterin directly influences cell death is lacking. Following neonatal H-I brain injury in mice (a model of cerebral palsy), there was evidence of apoptotic changes (neuronal caspase-3 activation), as well as accumulation of clusterin in dying neurons. Clusterin-deficient mice had 50% less brain injury following neonatal H-I. Surprisingly, the absence of clusterin had no effect on caspase-3 activation, and clusterin accumulation and caspase-3 activation did not colocalize to the same cells. Studies with cultured cortical neurons demonstrated that exogenous purified astrocyte-secreted clusterin exacerbated oxygen/glucose-deprivation-induced necrotic death. These results indicate that clusterin may be a new therapeutic target to modulate non-caspase-dependent neuronal death following acute brain injury.

BDNF protects against spatial memory deficits following neonatal hypoxia-ischemia

Hypoxic-ischemic (H-I) brain injury in the human perinatal period often leads to significant long-term neurobehavioral dysfunction in the cognitive and sensory-motor domains. Using a neonatal H-I injury model (unilateral carotid ligation followed by hypoxia) in postnatal day seven rats, previous studies have shown that neurotrophins, such as brain-derived neurotrophic factor (BDNF), can be protective against neural tissue loss. The present study explored potential relationships between neural protective and behavioral protective strategies in this neonatal H-I model by determining if neonatal H-I was associated with behavioral spatial learning and memory deficits and whether the neurotrophin BDNF was protective against both brain injury and spatial learning/memory dysfunction. Postnatal day seven rats received vehicle or BDNF pretreatments (intracerebroventricular injections) followed by H-I or sham treatments and then tested for spatial learning and memory on the simple place task in the Morris water maze from postnatal days 20 to 30, and their brains were histologically analyzed at 4 weeks following treatments. H-I rats with vehicle pretreatment displayed significant tissue loss in the hippocampus (including CA1 neurons), cortex, and striatum, as well as severe spatial memory deficits (e.g., short probe times). BDNF pretreatment resulted in significant protection against both H-I-induced brain tissue losses and spatial memory impairments. These findings indicate that unilateral H-I brain injury in a neonatal rodent model is associated with cognitive deficits, and that BDNF pretreatment is protective against both brain injury and spatial memory impairment.

BDNF protects the neonatal brain from hypoxic-ischemic injury in vivo via the ERK pathway

Neurotrophins activate several different intracellular signaling pathways that in some way exert neuroprotective effects. In vitro studies of sympathetic and cerebellar granule neurons have demonstrated that the survival effects of neurotrophins can be mediated via activation of the phosphatidylinositol 3-kinase (PI3-kinase) pathway. Neurotrophin-mediated protection of other neuronal types in vitro can be mediated via the extracellular signal-related protein kinase (ERK) pathway. Whether either of these pathways contributes to the neuroprotective effects of neurotrophins in the brain in vivo has not been determined. Brain-derived neurotrophic factor (BDNF) is markedly neuroprotective against neonatal hypoxic-ischemic (H-I) brain injury in vivo. We assessed the role of the ERK and PI3-kinase pathways in neonatal H-I brain injury in the presence and absence of BDNF. Intracerebroventricular administration of BDNF to postnatal day 7 rats resulted in phosphorylation of ERK1/2 and the PI3-kinase substrate AKT within minutes. Effects were greater on ERK activation and occurred in neurons. Pharmacological inhibition of ERK, but not the PI3-kinase pathway, inhibited the ability of BDNF to block H-I-induced caspase-3 activation and tissue loss. These findings suggest that neuronal ERK activation in the neonatal brain mediates neuroprotection against H-I brain injury, a model of cerebral palsy.

No effect of apolipoprotein E on neuronal cell death due to excitotoxic and apoptotic agents in vitro and neonatal hypoxic ischaemia in vivo

The epsilon4 allele of apolipoprotein E (apoE) is a genetic risk factor for Alzheimer's disease. Studies also suggest that the epsilon4 allele may be a risk factor for poor outcome following head trauma, brain haemorrhage and ischaemia. The mechanism by which the presence of an apoE epsilon4 allele and certain brain injuries act to predispose to Alzheimer's disease and poor outcome following brain injury is unknown. We questioned whether poor outcome after brain injury was due to direct modification by apoE protein and its gene variants of susceptibility to glutamate-mediated excitotoxic injury and apoptosis, mechanisms of cell death which occur following ischaemia and trauma. We investigated the effect of the presence or absence of endogenous murine apoE protein and different apoE isoforms in modification of the survival of murine embryonic cortical neurons exposed to the glutamate agonist, N-methyl-D-aspartic acid (NMDA) or apoptotic insult by staurosporine, and on the amount of brain injury sustained following a hypoxic-ischaemic insult in vivo to the brain of neonatal mice transgenically expressing human apoE epsilon3 or epsilon4. Our data provide evidence that apoE does not appear to alter neuronal viability following diverse types of acute neuronal insult, e.g. hypoxic-ischaemic or acute exposure to injurious agents in the models we have examined. This suggests that if apoE does modify the extent of brain damage and recovery after injury, it seems unlikely to be a result of direct or indirect modulation of excitotoxic or apoptotic cell death.

Furosemide stimulates K transport in HCD57 erythroid cells

We examined the influence of serum and furosemide on K movement and cell volume in HCD57 cells, a murine erythroleukemia cell line, which require erythropoietin (EPO) for survival. We found that maintenance of cell volume depends on the concentration of serum in the culture medium. In isotonic medium containing 20% serum, HCD57 cells maintain their steady-state volume. In contrast, the cells shrink progressively as medium serum content is reduced. In serum-free medium, raising external K to 75 mm prevents cell shrinkage and a further increase in K to 145 mm results in swelling, revealing a role for K permeability in the regulation of cell volume. Of particular interest has been a serendipitous finding with furosemide. Below an external K concentration of 2.1 +/- 0.3 mm in medium containing 2% serum, furosemide inhibits K uptake, probably stemming from its well known inhibitory action on KCl cotransport. However, above that K concentration, furosemide stimulates K uptake in a dose-dependent manner. Moreover, furosemide potentiates cell shrinkage induced by serum withdrawal. These findings suggest that the transport machinery mediating cellular shrinkage, once primed by serum depletion, becomes receptive to a second stimulus.

BDNF blocks caspase-3 activation in neonatal hypoxia-ischemia

Hypoxic-ischemic (H-I) injury to the brain in the perinatal period often leads to significant long-term neurological deficits. In a model of neonatal H-I injury in postnatal day 7 rats, our previous data have shown that cell death with features of apoptosis is prominent between 6 and 24 h after H-I and that neurotrophins, particularly BDNF, can markedly protect against tissue loss. During brain development, caspase-3 is required for normal levels of programmed cell death. Utilizing an antibody specific for the activated form of caspase-3, CM1, we now show that caspase-3 is specifically activated in neuronal cell bodies and their processes beginning at 6 h and peaking 24 h following unilateral carotid ligation and exposure to hypoxia in postnatal day 7 rats. Caspase-3 activation began to occur in cortex at 6 h and in striatum and hippocampus at 12-18 h. Caspase-3 activation was also observed in developing oligodendrocytes. Intracerebroventricular injection of BDNF prior to H-I injury almost completely abolished evidence of H-I-induced caspase-3 activation in vivo. Utilizing a specific molecular marker of an apoptotic pathway, these findings demonstrate that H-I injury to the developing brain is a strong apoptotic stimulus leading to caspase-3 activation, that BDNF can block this process in vivo, and that the ability of BDNF to inhibit caspase activation and subsequent apoptosis likely accounts in large part for its protection against neuronal injury in this model.