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Background: Although central venous occlusion is sometimes seen in hemodialysis (HD) patients, neurological symptoms due to intracranial venous reflux (IVR) are extremely rare. Case Description: We present a case of a 73-year-old woman with cerebral hemorrhage due to IVR associated with HD. She presented with lightheadedness and alexia, and was diagnosed with subcortical hemorrhage. Venography through the arteriovenous graft showed occlusion of the left brachiocephalic vein (BCV) and IVR through the internal jugular vein (IJV). It is extremely rare that IVR occurs and causes neurological symptoms. This is because that there is the presence of a valve in the IJV and the communication between the right and left veins through the anterior jugular vein and thyroid vein. Percutaneous transluminal angioplasty for the left obstructive BCV was performed, but the obstructive lesion was only slightly improved. Hence, shunt ligation was performed. Conclusion: When IVR is found in HD patients, central veins should be confirmed. Early diagnosis and therapeutic intervention are desirable when neurological symptoms are present.

Background and Purpose: High blood pressure increases bleeding risk during treatment with antithrombotic medication. The association between blood pressure levels and the risk of recurrent stroke during long-term secondary stroke prevention with thienopyridines (particularly prasugrel) has not been well studied. Methods: This was a post hoc analysis of the randomized, double-blind, multicenter PRASTRO-I trial (Comparison of Prasugrel and Clopidogrel in Japanese Patients With Ischemic Stroke-I). Patients with noncardioembolic stroke were randomly assigned (1:1) to receive prasugrel 3.75 mg/day or clopidogrel 75 mg/day for 96 to 104 weeks. Risks of any ischemic or hemorrhagic stroke, combined ischemic events, and combined bleeding events were determined based on the mean level and visit-to-visit variability, including successive variation, of systolic blood pressure (SBP) throughout the observational period. These risks were also compared between quartiles of mean SBP level and successive variation of SBP. Results: A total of 3747 patients (age 62.1±8.5 years, 797 women), with a median average SBP level during the observational period of 132.5 mm Hg, were studied. All the risks of any stroke (146 events; hazard ratio, 1.318 [95% CI, 1.094–1.583] per 10-mm Hg increase), ischemic stroke (133 events, 1.219 [1.010–1.466]), hemorrhagic stroke (13 events, 3.247 [1.660–6.296]), ischemic events (142 events, 1.219 [1.020–1.466]), and bleeding events (47 events, 1.629 [1.172–2.261]) correlated with increasing mean SBP overall. Similarly, an increased risk of these events correlated with increasing successive variation of SBP (hazard ratio, 3.078 [95% CI, 2.220–4.225] per 10-mm Hg increase; 3.051 [2.179–4.262]; 3.276 [1.172–9.092]; 2.865 [2.042–4.011]; 2.764 [1.524–5.016], respectively). Event rates did not differ between the clopidogrel and prasugrel groups within each quartile of SBP or successive variation of SBP. Conclusions: Both high mean SBP level and high visit-to-visit variability in SBP were significantly associated with the risk of recurrent stroke during long-term medication with either prasugrel or clopidogrel after stroke. Control of hypertension would be important regardless of the type of antiplatelet drugs. Registration: URL: https://www.clinicaltrials.jp ; Unique identifier: JapicCTI-111582.

Intracranial cerebral atherosclerosis is a significant predictor of stroke after coronary artery bypass grafting (CABG). However, there is limited information on intracranial occlusive lesions in patients undergoing CABG. The purpose of the study was to elucidate the precise prevalence and distribution of occlusive lesions of the extracranial and intracranial arteries in patients undergoing CABG. Between 2009 and 2016, 205 patients underwent preoperative magnetic resonance angiography and elective CABG. The prevalence and the distribution of occlusive lesions were retrospectively examined by preoperative magnetic resonance angiography. Association between postoperative central nervous system (CNS) complications and the occlusive lesions was analyzed. Fifty-six patients (27.3%) and 60 patients (29.3%) had occlusive lesions of the extracranial and intracranial arteries, respectively. Twenty-eight patients (13.7%) had both extracranial and intracranial occlusive lesions. Thirty-one (15.1%) and 45 (22.0%) patients had severe stenosis or occlusion of the extracranial and intracranial arteries, respectively. The intracranial internal carotid artery was the most commonly affected intracranial artery (60 vessels; 62.5%), followed by the middle cerebral arteries (20 vessels; 20.8%). Sixteen patients (7.8%) suffered from postoperative CNS complications, including 2 permanent strokes. The etiology of the stroke was attributable to a predefined intracranial lesion in 1 patient. In multivariate analysis, the presence of intracranial occlusive lesions was found to have an independent association with the development of CNS complications (odds ratio 4.05; 95% confidence interval 1.13-14.6). The prevalence of intracranial occlusive lesions was higher than that of extracranial lesions in patients undergoing CABG. There was a solid trend toward the anterior distribution of the intracranial occlusive lesions.

There are 2 kinds of surgical approaches to unruptured anterior communicating artery aneurysm (Acom an): the pterional and interhemispheric approach. Currently, the thoice of approach depends on the surgeon’s preference and experience. In our study, we compared the interrelationship between appropriate surgical approach and dome projection among the following 3 groups: anterior/inferior, superior, and posterior projections. The results showed only aneurysms with anterior/inferior dome projection were suitable for the pterional approach. However, the interhemispheric approach was preferable for aneurysms with all other projections except for anterior/inferior projection. Surgeons should be familiar with both approaches so they we can select according to dome projection of Acom an.

Three-dimensional CT angiography (3D-CTA) is a useful modality for planning in clipping surgery of cerebral aneurysms. In addition, maximum intensity projection (MIP) technique allows easy visualization of intramural calcification around the aneurysm. In the present study, we compared preoperative findings with intraoperative findings regarding atherosclerosis and encountered 2 cases of unruptured aneurysm with unexpected severe atherosclerosis, which considered potential limitations to the use of MIP image for preoperative planning. We discuss surgical techniques for both cases when the wall of the aneurysm and neighboring arteries are thick and atherosclerotic.

We provide intraoperative problems and their preventive measures during the pterional approach to the basilar top aneurysm. We focus on the surgical techniques to obtain a wider operative field through the pterional approach. The surgical difficulties depend on various factors, including the size, location, and direction of the basilar top aneurysm. In particular, the interrelationship between the location of the internal carotid artery and the basilar top aneurysm is an important factor to be fully assessed preoperatively.

It has been believed that clinical outcomes of the elderly subarachnoid hemorrhage (SAH) patients in poor grades are quite unsatisfactory. Recently, endovascular coil embolization is available for such patients as a less invasive treatment. In this study, we retrospectively analyzed clinical outcome of SAH patients in poor grades who were treated with endovascular coil embolization. Among 54 patients (≧75 years) presenting aneurysmal SAH who underwent early endovascular coil embolization, 24 patients in WFNS Grade IV or V were analyzed. Nineteen patients were in Grade IV, and 5 patients in Grade V. In all the patients, the dome of the aneurysm was successfully embolized with detachable coils. The degree of occlusion of the treated aneurysm was complete occlusion in 21%, neck remnant in 33%, dome filling in 25%, and partial in 21%. The rate of procedural complication was 8.3%. Outcome after 6 months was favorable in 37% of Grade IV and 40% in Grade V, respectively. Endovascular coil embolization was successfully performed in elderly SAH patients in poor neurological grades with a high level of technical success and acceptable clinical outcomes.

The present study was designed to examine the roles of p53, reactive oxygen species (ROS), and ceramide, and to determine their mutual relationships during tumor necrosis factor (TNF)-alpha-induced apoptosis of human glioma cells. In cells possessing wild-type p53, TNF-alpha stimulated ceramide formation via the activation of both neutral and acid sphingomyelinases (SMases), accompanied by superoxide anion (O2-*) production, and induced mitochondrial depolarization and cytochrome c release, whereas p53-deficient cells were partially resistant to TNF-alpha and lacked O2-* generation and neutral SMase activation. Restoration of functional p53 sensitized glioma cells expressing mutant p53 to TNF-alpha by accumulation of O2-*. z-IETD-fmk (benzyloxycarbonyl-Ile-Glu-Thr-Asp fluoromethyl ketone), but not z-DEVD-fmk (benzyloxycarbonyl-Asp-Glu-Val-Asp fluoromethyl ketone), blocked TNF-alpha-induced ceramide formation through both SMases as well as O2-* generation. Caspase-8 was processed by TNF-alpha regardless of p53 status of cells or the presence of antioxidants. Two separate signaling cascades, p53-mediated ROS-dependent and -independent pathways, both of which are initiated by caspase-8 activation, thus contribute to ceramide formation in TNF-alpha-induced apoptosis of human glioma cells.

Programmed cell death, or apoptosis, is a tightly regulated, naturally occurring process by which damaged or unwanted cells are removed. Dysregulated apoptosis has been implicated in a variety of pathophysiological conditions, including degenerative diseases, tissue remodeling, and tumorogenesis. The decision to live or die results from integration of numerous environmental signals transmitted by specific classes of cell surface receptors that bind hormones, growth factors, or components of the extracellular matrix. Here we show that platelet endothelial cell adhesion molecule-1 (PECAM-1), a homophilic-binding member of the immunoreceptor tyrosine-based inhibitory motif (ITIM) family of inhibitory receptors, functions prominently to inhibit apoptosis in naturally occurring vascular cells subjected to apoptotic stimuli. Murine endothelial cells and human T lymphocytes lacking PECAM-1 were found to be far more sensitive than their PECAM-1—expressing counterparts to multiple death signals that stimulate Bax, a multidomain, proapoptotic member of the Bcl-2 family that plays a central role in mitochondrial dysfunction-dependent apoptosis. In addition, PECAM-1 markedly suppressed Bax overexpression—induced cytochrome c release, caspase activation, and nuclear fragmentation. Amino acid substitutions within PECAM-1's extracellular homophilic binding domain, or within its cytoplasmic ITIM, completely abolished PECAM-1—mediated cytoprotection. Taken together, these data implicate PECAM-1 as a novel and potent suppressor of Bax-mediated apoptosis and suggest that members of the immunoglobulin gene (Ig) superfamily, like cell surface integrins, may also transmit survival signals into blood and vascular cells. (Blood. 2003;102:169-179)

Bax is a pro-apoptotic member of Bcl-2 family proteins and is central to mitochondria-dependent apoptosis. Bax resides in the cytosol as a quiescent protein and translocates into mitochondria after apoptotic stimuli. Ku70 is a 70K subunit of the Ku complex, which has an important role in DNA double-strand break (DSB) repair in the nucleus. In another article in this issue, we reported that Ku70 interacts with pro-apoptotic protein Bax in the cytosol and prevents its mitochondrial translocation, suggesting that Ku70 suppresses Bax-mediated apoptosis. Here, we describe the development of a new membrane-permeable peptide, Bax-inhibiting peptide (BIP) that inhibits Bax-mediated apoptosis, on the basis of the previous finding that showed an interaction between Ku70 and Bax. BIP is comprised of five amino acids designed from the Bax-binding domain of Ku70, and suppresses the mitochondrial translocation of Bax. BIP inhibited Bax-mediated apoptosis induced by staurosporine, UVC irradiation and anti-cancer drugs in several types of cells. BIP may provide valuable information in the development of therapeutics that control apoptosis-related diseases.

Bax induces mitochondrial-dependent cell death signals in mammalian cells. However, the mechanism of how Bax is kept inactive has remained unclear. Yeast-based functional screening of Bax inhibitors from mammalian cDNA libraries identified Ku70 as a new Bax suppressor. Bax-mediated apoptosis was suppressed by overexpression of Ku70 in mammalian cells, but enhanced by downregulation of Ku70. We found that Ku70 interacts with Bax, and that the carboxyl terminus of Ku70 and the amino terminus of Bax are required for this interaction. Bax is known to translocate from the cytosol to mitochondria when cells receive apoptotic stimuli. We found that Ku70 blocks the mitochondrial translocation of Bax. These results suggest that in addition to its previously recognized DNA repair activity in the nucleus, Ku70 has a cytoprotective function in the cytosol that controls the localization of Bax.

The role of superoxide anion (O(2)*-) in neuronal cell injury induced by reactive oxygen species (ROS) was examined in PC12 cells using pyrogallol (1,2,3-benzenetrior), a donor to release O(2)*-. Pyrogallol induced PC12 cell death at concentrations, which evidently increased intracellular O(2)*-, as assessed by O(2)(*-)-sensitive fluorescent precursor hydroethidine (HEt). Caspase inhibitors, Z-VAD-FMK and Z-Asp-CH(2)-DCB, failed to protect cells from injury caused by elevation of intracellular O(2)*-, although these inhibitors had effects on hypoxia- or hydrogen peroxide (H(2)O(2))-induced PC12 cell death. Two known O(2)*- scavengers, Tiron (4,5-dihydroxy-1,3-benzenedisulfonic acid) and Tempol (4-hydroxy-2,2,6,6-tetramethylpiperydine-1-oxyl) rescued PC12 cells from pyrogallol-induced cell death. Hypoxia/reoxygenation injury of PC12 cells was also blocked by Tiron and Tempol. Further understanding of the underlying mechanism of the protective effects of these radical scavengers reducing intracellular O(2)*- on neuronal cell death may lead to development of new therapeutic treatments for hypoxic/ischemic brain injury.

We have investigated to determine the source of ceramide produced during the genotoxic apoptosis induced by the anti-cancer drug, camptothecin (CPT), in human prostate cancer LNCaP cells by measuring the activities of acid and neutral sphingomyelinases (SMase) and by using fumonisinB(1) (FB(1)), the inhibitor of ceramide synthase involving de novo synthesis of ceramide. In contrast to time-dependent elevation of intracellular ceramide level after CPT-treatment, the activities of both SMases were not increased but rather decreased. Instead, pretreatment for 3 h with FB(1) (100 microM), an inhibitor of ceramide synthase, almost completely abrogated ceramide accumulation observed in cells exposed to CPT for 18 h. These results indicate that ceramide is produced via de novo pathway but not via sphingomyelin hydrolysis pathway. Furthermore, it is to be noted that the pretreatment with FB(1) did not affect the CPT-induced apoptosis as assessed by DNA ladder formation, Hoechst 33342 staining, flow cytometry, and mitochondrial potential thereby leading us to propose that ceramide accumulation is independent of apoptosis in this system.

Ca2+ influx is one of the main causative events in hypoxic PC12 cell death, because an extracellular Ca2+ chelator, ethylene glycol bis (2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) inhibited and Ca2+ ionophore A23187 mimicked the hypoxic cell death. The hypoxic cell death was markedly prevented by a broad spectrum caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-FMK) as well as a calpain inhibitor, calpeptin, as assessed by nuclear staining with Hoechst 33258 and lactate dehydrogenase release. The processing of procaspase-3 was inhibited by z-VAD-FMK, but not by calpeptin. In contrast, z-VAD-FMK failed to block the proteolytic cleavage of fodrin-alpha, a preferential substrate for calpain. On the other hand, degradation of actin and fodrin-alpha was prevented by calpeptin but not by z-VAD-FMK. In addition, not only protein kinase C (PKC)-alpha but also PKC-delta were cleaved to generate approximately 46 kDa fragments. The PKC fragmentation was inhibited by calpeptin but not by z-VAD-FMK. These findings suggest that the extracellular Ca2+ influx induced by hypoxic stress activates calpain, resulting in the degradation of cytoskeletal proteins and generation of PKC fragments almost independently of caspase activation. Therefore, calpain may play an important role in hypoxic PC12 cell death.

Cisplatin is commonly used for the treatment of malignant brain tumors. However, the mechanisms of cell death by cisplatin are not fully understood. Therefore, the present study was designed to elucidate the apoptotic signaling pathway(s) activated by cisplatin in a C6 rat glioma cell line. C6 cells were treated with various concentrations of cisplatin (0.2-10 microg/ml) for 24-72 h. At 10 microg/ml cisplatin, over 90% of the cells became dead at 72 h. Apoptotic death was confirmed by condensation and fragmentation of nuclei, and DNA laddering. Even in cells treated with 1.5 microg/ml cisplatin, typical apoptotic cells were observed at 72 h. The intracellular level of ceramide, measured Escherichia coli diacylglycerol kinase markedly increased during 24-72 h after the addition of 10 microg/ml cisplatin. The activity of caspase-3(-like) proteases increased and reached a peak at 48 h. Inhibitors of caspases reduced the number of apoptotic cells. Pretreatment of C6 cells with glutathione or N-acetyl-cysteine, which are known to block the activation of neutral magnesium-dependent sphingomyelinase, inhibited ceramide formation, leading to suppression of both activation of caspase-3(-like) proteases and apoptosis by cisplatin. In contrast, pretreatment of the cells with N-oleoylethanolamine (OE), a ceramidase inhibitor, potentiated apoptosis induced by cisplatin. Furthermore, OE enhanced sensitivity of the cisplatin-resistant cells to cisplatin. These results suggest that ceramide is closely implicated in apoptosis of glioma cells by cisplatin through activation of caspase-3(-like) proteases.

Calcium-elevating protein cross-reacted with anti-human transferrin (TF) was purified in cerebrospinal fluid (CSF) after subarachnoid hemorrhage (SAH). The concentration of TF in CSF after SAH was measured, and the effects of TF on cultured smooth muscle cells (SMCs) were evaluated in order to understand the relationship between TF and cerebral vasospasm. Cisternal CSF samples were collected from 12 patients (seven men and 13 women) with SAH due to the rupture of a cerebral aneurysm, and eight control subjects. The patients were divided into two groups: (1) those presenting no clinical and radiological evidence of vasospasm (the non-vasospasm group; three men and 10 women, mean age 54.7 years), and (2) those presenting evidence of vasospasm (the vasospasm group; four men and three women, mean age 58.3 years). The concentration of TF in CSF was measured using Speriol micro-transferrin measure assay method. Nitrite accumulation in the culture media of SMCs incubated with TF was determined by diazotization method. The mRNA levels of inducible isoform of NOS (iNOS) in SMC incubated with TF were measured by the reverse transcription-coupled polymerase chain reaction method. Levels of TF were markedly different in the SAH and the control subjects. In the control group, all subjects had no detectable quantity of TF. In contrast, all patients after SAH had quantifiable TF in their CSF. Moreover, there was a significant difference between the vasospasm group and the non-vasospasm group in TF levels (p < 0.05). In the vasospasm group, the average value was 10.43 +/- 2.8 mg dl-1. In the non-vasospasm group, the average was 3.69 +/- 0.31 mg dl-1. The nitrite content in the culture medium incubated with TF was three times the content of control. TF also induced iNOS mRNA in SMC. This study demonstrated that an elevation of TF concentration in CSF after SAH was detected and iNOS mRNA in SMCs was also induced by TF. This may be involved in some roles of the development of the pathological series of events after SAH, including vasospasm.

The treatment of PC12 cells with H2O2 (100-500 microM) resulted in typical apoptotic changes including fragmentation and condensation of nuclei, and DNA fragmentation observed as DNA ladder. H2O2-induced apoptosis was associated with activation of caspase-3 as assessed by cleavage of specific fluorogenic substrate peptide and processing of procaspase-3 and poly(ADP-ribose) polymerase. However, formation of ceramide, which often locates upstream of caspase-3, was not observed. The inhibitory peptide relatively specific for caspase-3, z-DEVD-FMK and non-selective caspase inhibitor z-VAD-FMK inhibited activation of caspase-3 and apoptotic cell death. However, the relatively specific inhibitors, Ac-YVKD for caspase-1 and Ac-IETD for caspase-8/6, did not affect the occurrence of apoptotic cell death. As an upstream activation of caspase-3, induction of cytochrome c release followed by processing of procaspase-9 was observed by Western blotting, although the formation of intracellular ceramide was not observed. On the other hand, in PC12 cells overexpressing Bcl-2, the number of apoptotic cells was markedly decreased and activation of both caspases-9 and -3 was prevented. These results suggest that cytochrome c and caspase-9 initiate the activation of executor caspase-3 in H2O2-treated PC12 cells, and that Bcl-2 inhibits H2O2-induced release of cytochrome c from mitochondria and then proteolytic processing of procaspase-9.

Etoposide (VP-16) a topoisomerase II inhibitor induces apoptosis of tumor cells. The present study was designed to elucidate the mechanisms of etoposide-induced apoptosis in C6 glioma cells. Etoposide induced increased formation of ceramide from sphingomyelin and release of mitochondrial cytochrome c followed by activation of caspase-9 and caspase-3, but not caspase-1. In addition, exposure of cells to etoposide resulted in decreased expression of Bcl-2 with reciprocal increase in Bax protein. z-VAD.FMK, a broad spectrum caspase inhibitor, failed to suppress the etoposide-induced ceramide formation and change of the Bax/Bcl-2 ratio, although it did inhibit etoposide-induced death of C6 cells. Reduced glutathione or N-acetylcysteine, which could reduce ceramide formation by inhibiting sphingomyelinase activity, prevented C6 cells from etoposide-induced apoptosis through blockage of caspase-3 activation and change of the Bax/Bcl-2 ratio. In contrast, the increase in ceramide level by an inhibitor of ceramide glucosyltransferase-1, D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol caused elevation of the Bax/Bcl-2 ratio and potentiation of caspase-3 activation, thereby resulting in enhancement of etoposide-induced apoptosis. Furthermore, cell-permeable exogenous ceramides (C2- and C6-ceramide) induced downregulation of Bcl-2, leading to an increase in the Bax/Bcl-2 ratio and subsequent activation of caspases-9 and -3. Taken together, these results suggest that ceramide may function as a mediator of etoposide-induced apoptosis of C6 glioma cells, which induces increase in the Bax/Bcl-2 ratio followed by release of cytochrome c leading to caspases-9 and -3 activation.

Ceramide has recently been regarded as a potential mediator of apoptosis. In the present study, the effects of Bcl-2 and Bax on the ceramide-mediated apoptotic pathways were examined in glioma cells overexpressing Bcl-2 or Bax. Etoposide, cisplatin and tumor necrosis factor-alpha induced apoptosis of C6 rat glioma cells which was associated with ceramide formation due to activation of neutral sphingomyelinase, followed by release of mitochondrial cytochrome c into the cytosol and activation of caspases-9 and -3. The growth of C6 cells stably overexpressing either Bcl-2 or Bax was almost equal to that of the vector-transfected cells. Bax overexpression enhanced etoposide-induced apoptosis through acceleration of cytochrome c release and caspases activation. However, Bax had no effect on ceramide formation. Similar findings were obtained in C6 cells and U87-MG human glioblastoma cells which were transiently overexpressed with Bax. In contrast, Bcl-2 overexpression resulted in a retardation of the apoptotic process via prevention of cytochrome c release and caspases activation, and ceramide formation was also blocked when Bcl-2 was highly overexpressed in glioma cells. In addition, transient overexpression of Bcl-xL also exerted inhibitory effects on ceramide formation and apoptotic cell death induced by etoposide. These results indicate that Bax promotes apoptosis regardless of ceramide formation and that Bcl-2 or Bcl-xL prevents ceramide formation by repressing neutral sphingomyelinase as well as ceramide-induced cytochrome c release. Oncogene (2000) 19, 3508 - 3520

BACKGROUND Osteoplastic craniotomy has been performed recently with microfixation systems such as miniplates, burr hole buttons, and/or ceramic dust. However, these are costly methods of treatment. Without the use of these devices, we performed cosmetic osteoplastic craniotomy using an inexpensive chisel and hammer. METHODS Our osteoplastic craniotomy with a chisel and hammer was used on 19 lesions in 15 patients. Using a chisel, the bone flap was cut gently from the calvarium to the skull base, the lamina externa to the diploe (finally the lamina interna), and both ends to the midportion between two holes. The lamina interna in the cranium was trimmed easily after removal of the bone flap. The bone defect was minimal because of the absence of a narrow cutting groove and because craniectomy was not performed. The bone flap was replaced by tapping and was tightly fixed. No special fixation system was needed, except for threads. RESULTS Follow-up (mean follow-up, 5 months; range, 5 weeks to 9 months) skull X-ray and 3D-CT showed good fusion and inherent normal configuration of the bone flap. There were two minor dural tears and two minor bony fractures. CONCLUSION A good cosmetic effect without the use of any additional instruments was accomplished with osteoplastic craniotomy using a chisel and hammer.

We report excellent initial results of stenting for stenosis of major cerebral arteries experienced between April 1997 and June 1998. Patients ranged in age from 61 to 78 year old (mean 65 year old). The location of the lesion included cervical carotid artery: 10, orifice of vertebral artery: 3, subclavian artery: 3. All lesion were high grade more than 60%. Ten were symptomatic (TIA 5, minor stroke 1, VBI 2. others 2), and six were asymptomatic. Stents utilized were Palmaz stents, the balloon expandable type originally developed for peripheral arteries. Stents were placed at the lesion after predilatation in some patients and primarily in other patients. Almost complete dilatation was obtained in every patient without any permanent adverse event. Bradycardia and mild hypotension due to vaso-vagal reflex was observed in two patients with carotid stenosis until next day after treatment. TIA was experienced in two patients with carotid stenosis. No further ischemic events were observed during the short-term follow-up period. Usefulness of stenting for major cerebral artery stenosis was indicated by our initial results. Stenting will play an important role in the treatment of cerebrovascular disease in the near future, though the development of better stents for the cerebral arteries and long-term follow-up are mandatory.

OBJECTIVE: Percutaneous transluminal angioplasty (PTA) is accepted as a safe and effective procedure for the treatment of stenotic arterial lesions of various sites. However, distal embolism may cause serious complications in the PTA of cephalic arteries. By monitoring embolic signals using transcranial Doppler (TCD) ultrasonography, we speculated regarding the safety and/or risk of PTA for vertebral and subclavian artery stenosis. METHODS: Twelve consecutive patients undergoing PTA for subclavian and vertebral artery stenosis of atherosclerotic origin were studied. All patients were refractory to initial medical treatment and were considered for PTA. During the PTA procedure, all patients were heparinized. Before, during, and after PTA, TCD monitoring was performed to detect embolic signals for 30 minutes at each time. After PTA, anticoagulant and antiplatelet therapies were continued in all patients. RESULTS: Before, during, and after PTA, a steady flow signal could be obtained from each vertebral artery monitored using TCD ultrasonography. No embolic signals were detected in any patient before angioplasty. During angioplasty, one embolic signal was detected immediately after balloon deflation in 1 of 12 patients. Several embolic signals were detected after the procedure in 6 of 12 patients, but thereafter embolic signals became less frequent in number. Three days after angioplasty, embolic signals were not detected in any patient. There were no serious complications caused by the PTA procedure. CONCLUSION: TCD monitoring may be a useful modality for detection of microemboli during and after PTA in the posterior circulation. We suspected that subclinical microemboli are released from the dilated vessels for 3 days after vertebral and subclavian PTA and that anticoagulant or antiplatelet therapies may prevent embolic complications after the procedure.

過去15年間の特発性頸動脈海綿静脈洞痩 (CdAVF) 50例に対する血管内手術とその問題点を検討した.男13例, 女37例, 平均年齢は57歳 (23歳から79歳) である.1例は未治療である.39例は最終的に経静脈的塞栓術 (TVE) を行い36例で治癒を, 3例で改善を得た。手技的には下錐体静脈洞 (IPS), 上眼静脈 (SOV) あるいは外頸静脈 (EJ) 経由にて痩孔を含めた海綿静脈洞 (CS) の閉塞を行った.10例で外頸動脈枝あるいは内頸動脈を閉塞し8例で治癒を得た.塞栓物質はブドウ糖, PVA粒子, 銅線, EVAL, コイル等を用いた.合併症として脳内出血が2例見られた.シャント量が少ない症例では経動脈的塞栓術も効果がみられた.痩孔部を閉塞することが原則だがSOV, 蝶形頭頂静脈洞等の皮質静脈, 痩孔の順に閉塞するのが確実である.IPS, CSの状態によりIPS経由でアプローチできないことがあり他のルートをとる必要がある.静脈還流障害の高度な症例では静脈性高血圧による梗塞を起こす可能性があるのでSOVの閉塞と痩孔部の閉塞は一期的に行わねばならない.症例によりその手技を微妙に使い分けることによりCdAVFに対する経静脈的アプローチがより安全, 確実に行われる.

A 27-year-old male presented with intracranial hemorrhage due to rupture of an idiopathic dissecting aneurysm in the A4 segment of the left anterior cerebral artery (ACA). This is a very rare location. He was successfully treated by resection of the aneurysm without neurological deficits. Surgical intervention is recommended for patients with intracranial hemorrhage due to ruptured dissecting aneurysm of the ACA to prevent rebleeding.

We successfully performed endovascular coil embolization for 2 patients with unruptured saccular aneurysms. However, transient cortical blindness and generalized seizure associated with CNS neurotoxity of contrast medium were noted for each patient after the procedure. In the first case of a 62-year-old woman with a right BA-SCA aneurysm, she complained of blindness with restlessness one day after the intervention but no evidence of embolism on MRA. Abnormal EEG with slow, large amplitudes and 99mTc-HMPAO SPECT-evidenced hyperperfusion were observed in the occipital area. Accompanied by resolution of the edematous changes on MRI in conjunction with normalization of EEG and rCBF by anticonvulsant administration, her visual acuity completely recovered 8 days after the onset. According to these findings, we considered this case as transient cortical blindness. In the second case of a 68-year-old man with a left MCA aneurysm, he exhibited generalized seizure 8 hours after the procedure. CT scan revealed retention of the contrast medium over the left hemisphere. Postictal EEG one day after the seizure showed left frontal slowing but had no evidence of contrast medium retention or hyperperfusion. He recovered well with corticosteroid, anticonvulsant, and intravenous hydration. His follow-up DSA 2 years after the coiling was performed without trouble by reducing the amount/concentration of the contrast medium and by prophylactic steroid and hydration. Non-ionic contrast medium-related neurotoxity as represented by transient cortical blindness or generalized seizure should be recognized as a possible complication of endovascular surgery where patients' brain areas are locally vulnerable to contrast medium exposure.

Endovascular treatment of intracranial aneurysms using platinum coils was performed in 26 patien with age over 70 years. The patients ranged from 70 to 86 years old (mean 77.5). Preoperative World Federation of Neurological Surgeons (WFNS) scale revealed that 6 patients were in grade I, 5 in grade II, 2 in grade III, 12 in grade IV, and 1 in grade V. The location of aneurysms are as follows; 10 were in the internal carotid artery, 7 in the anterior cerebral artery, 1 in the middle cerebral artery, and 8 in the vertebro-basilar system. Intra-aneurysmal occlusion was accomplished in 25 patients, resulting in 6 complete occlusion (24%), 3 neck remnant (12%), 11 body filling (44%), and both of neck remnant and body filling in 5 (20%). In one patient with vertebral artery union aneurysm, the parent artery was occluded just proximal to the aneurysm. Eleven of 13 patients with good clinical grade (grade I, II, and III) resulted in good clinical outcome, whereas 11 of 13 patients with poor clinical grade (grade IV and V) showed poor outcome. Periprocedural complications such as thromboembolism and intra-procedural rupture occurred in 5 patients (19.2%). Each of the complications was attributed to severe atherosclerotic changes of parent arteries. Symptomatic cerebral vasospasm occurred in only one patient (3.8%). In conclusion, endovascular coil emboilization is a useful therapeutic alternative for treating ruptured intracranial aneurysms in patients over 70 years of age, especially in patients with good clinical grade (better than grade III).

We have previously shown that treatment of human glioma U87-MG cells expressing wild-type p53 with a DNA topoisomerase II inhibitor, etoposide resulted in ceramide-dependent apoptotic cell death. However, U87-W E6 cells lacking functional p53 due to the expression of human papilloma virus type 16 (HPV-16) E6 oncoprotein were resistant to etoposide. In order to gain insight into the roles of p53 and ceramide in gamma-radiation-induced glioma cell death, we used U87-W E6 and vector-infected U87-LXSN cells. U87-LXSN glioma cells expressing wild-type p53 were relatively resistant to gamma-radiation. U87-W E6 cells, which lost functional p53, became susceptible to radiation-induced apoptosis. Activation of caspase-3, and formation of ceramide by acid sphingomyelinase, but not by neutral sphingomyelinase, were associated with p53-independent apoptosis. Radiation-induced caspase activation and apoptotic death in U87-W E6 cells were modified by the agents which affected ceramide metabolism. SR33557, an inhibitor of acid sphingomyelinase, suppressed radiation-induced caspase activation and then apoptotic cell death. In contrast, N-oleoylethanolamine (OE) and D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), which inhibit ceramidase and UDP-glucose:ceramide glucosyltransferase-1, respectively, and then augment ceramide formation, enhanced radiation-induced caspase activation. These results indicate that glioma cells with functional p53 were relatively resistant to gamma-radiation, and that ceramide may play an important role in caspase activation during gamma-radiation-induced apoptosis of glioma cells lacking functional p53.

Bax is a proapoptotic protein that plays a key role in the induction of apoptosis. Ku70 has activities to repair DNA damage in the nucleus and to suppress apoptosis by inhibiting Bax in the cytosol. We previously designed peptides based on the amino acid sequence of Bax-binding domain of human Ku70, and showed that these peptides bind Bax and inhibit cell death in human cell lines. In the present report, we examined the biological activities of other pentapeptides, VPTLK and VPALR, derived from mouse and rat Ku70. Cells in culture accumulated FITC-labeled VPTLK and VPALR, indicating that these peptides are cell permeable (human, mouse, rat, and porcine cells were examined). These peptides bound to Bax and suppressed cell death in various cell types including primary cultured cells. These data suggest that such Bax inhibiting peptides from three mammalian species may be used to protect healthy cells from apoptotic injury under pathological conditions.

Although the p53 tumor-suppressor gene product plays a critical role in apoptotic cell death induced by DNA-damaging chemotherapeutic agents, human glioma cells with functional p53 were more resistant to gamma-radiation than those with mutant p53. U-87 MG cells with wild-type p53 were resistant to gamma-radiation. U87-W E6 cells that lost functional p53, by the expression of type 16 human papillomavirus E6 oncoprotein, became susceptible to radiation-induced apoptosis. The formation of ceramide by acid sphingomyelinase (A-SMase), but not by neutral sphingomyelinase, was associated with p53-independent apoptosis. SR33557 (2-isopropyl-1-(4-[3-N-methyl-N-(3,4-dimethoxybphenethyl)amino]propyloxy)benzene-sulfonyl) indolizine, an inhibitor of A-SMase, suppressed radiation-induced apoptotic cell death. In contrast, radiation-induced A-SMase activation was blocked in glioma cells with endogenous functional p53. The expression of acid ceramidase was induced by gamma-radiation, and was more evident in cells with functional p53. N-oleoylethanolamine, which is known to inhibit ceramidase activity, unexpectedly downregulated acid ceramidase and accelerated radiation-induced apoptosis in U87-W E6 cells. Moreover, cells with functional p53 could be sensitized to gamma-radiation by N-oleoylethanolamine, which suppressed radiation-induced acid ceramidase expression and then enhanced ceramide formation. Sensitization to gamma-radiation was also observed in U87-MG cells depleted of functional p53 by retroviral expression of small interfering RNA. These results indicate that ceramide may function as a mediator of p53-independent apoptosis in human glioma cells in response to gamma-radiation, and suggest that p53-dependent expression of acid ceramidase and blockage of A-SMase activation play pivotal roles in protection from gamma-radiation of cells with endogenous functional p53.

The gene, termed r-gsp, was originally isolated during identification of differentiation-associated molecules in rat C6 glial cells. Its mRNA expression was markedly increased during cAMP-induced glial cell differentiation. The deduced amino acid sequence of r-gsp was homologous to those of complement C1s precursors of hamsters and humans. In the present study, we raised anti-peptide antibody against r-Gsp protein and analyzed its change during cAMP-induced differentiation. The 90-kDa r-Gsp protein increased time-dependently and reached the maximal level ( approximately 7.6-fold increase) at 24 h in response to dibutyryl cyclic AMP (dbcAMP) and theophylline. Moreover, it was secreted into the medium and then was cleaved to form disulfide-linked fragments, one of which was 30 kDa, similar to C1s, suggesting its processing in the extracellular space. In fact, the partially purified r-Gsp from culture medium was cleaved by active human C1r to form a 30-kDa polypeptide. Moreover, secreted r-Gsp protein cleaved human C4alpha to yield C4alpha' and associated with human serum C1-esterase inhibitor, strongly suggesting that r-Gsp protein is rat C1s. However, in C6 cells overexpressing r-Gsp, their morphology and proliferation rate were similar to those in parent C6 cells. These results suggest that r-Gsp protein could not induce glial differentiation alone, and suggest that r-Gsp protein was secreted as a proenzyme and processed in culture medium. Its possible role in glial cell differentiation will be discussed.

During apoptosis of human glioma cells induced by anti-Fas antibody, ceramide formation with activation of acid, but not neutral sphingomyelinase (SMase), was observed. A potent inhibitor of acid SMase, SR33557, effectively inhibited ceramide formation and apoptosis. Fas-induced apoptosis and ceramide formation proceeded regardless of p53 status. The agents, which modify intracellular levels of reactive oxygen species (ROS) and reduced glutathione (GSH), failed to modulate Fas-induced acid SMase activation and apoptosis. Moreover, expression of functional p53 protein using a temperature-sensitive human p53val 138 induced ceramide generation by activation of neutral SMase but not acid SMase through ROS formation. Peptide inhibitors for caspases-8 (z-IETD-fmk) and -3 (z-DEVD-fmk) suppressed Fas-induced apoptosis. However, activation of acid SMase was inhibited only by z-IETD-fmk. Thus, ceramide generated by acid SMase may take a part in Fas-induced apoptosis of human glioma cells and acid SMase activation may be dependent on caspase-8 activation, but not on p53 nor ROS.

Thrombin and the complement system are activated in vascular lesions during the process of atherosclerosis or pathologic proliferation of smooth muscle cells, and in the subarachnoid space during the development of cerebral vasospasm following subarachnoid hemorrhage (SAH). This article reviews the effects of a potent inhibitor of the complement system and/or thrombin on vascular neointimal formation in the carotid artery of rats, and the development of cerebral vasospasm following subarachnoid hemorrhage (SAH) in rabbits. Carotid balloon dilation injury induced in rats was treated with FUT-175 for 7 days. In rabbits, SAH was treated with FUT-175, or argatroban for 48 h. In addition, recombinant PDGF-BB was injected into the cisterna magna of normal rabbits to observe the calibers of the basilar arteries for 48 h. Neointimal formation after balloon injury was significantly reduced by the treatment with FUT-175. Development of cerebral vasospasm was prevented by FUT-175 or argatroban. In the histological examination, effective doses of FUT-175 or argatroban suppressed the expression of PDGF-BB in the neointimal lesions. Exogenous PDGF-BB resulted in delayed and prolonged vasoconstriction in normal basilar arteries. The complement system and/or thrombin activation following balloon dilation injury or SAH was demonstrated to play a critical role in the development of vascular lesion formation. In the cascade downstream of the protease activation, the production of PDGF-BB was indicated.

During hypoxic incubation (1% O2) of PC12 cells, the PLD activity was transiently increased within 12h, followed by a gradual decrease. In the in vitro assay, the increased PLD activity was independent of GTPgammaS required for PLD1 or of oleic acid for PLD(OA), suggesting the activation of PLD2. The level of PLD2 protein showed no change up to 12h but a gradual decrease after 24 h. Pretreatment of cells with S. chromofuscus PLD resulted in inhibition of hypoxia-induced apoptotic cell death. In contrast, 1-butanol, but not 2-butanol, potentiated cell death. Moreover, the number of apoptotic cells significantly reduced in PC12 cells over-expressing PLD2. These results raise the possibility that PLD2 activation may play an anti-apoptotic role in hypoxia-induced cell death.

The present study was designed to elucidate the relationship between p53 and ceramide, both of which are involved in apoptotic signaling. Treatment of human glioma cells with etoposide caused apoptosis only in cells expressing functional p53. p53 activation was followed by the formation of reactive oxygen species (ROS), superoxide anion (O2-*) measured by hydroethidium oxidation into ethidium and hydrogen peroxide (H2O2) measured by oxidation of 2',7'-dichlorofluorescin (DCFH) into 2',7'-dichlorofluorescein (DCF), which was accompanied with ceramide generation through the activation of neutral, but not acid, sphingomyelinase. Superoxide dismutase (SOD), a selective antioxidant for O2-*, had no effects on p53 expression but inhibited ceramide generation and apoptotic cell death caused by etoposide. However, catalase, a specific antioxidant for H2O2, only weakly inhibited and sodium formate, a hydroxyl radical (* OH) scavenger, unaffected etoposide-induced apoptosis. Like etoposide-induced cell death, treatment of glioma cells with the O2-*-releasing agent, pyrogallol, induced typical apoptosis and ceramide generation even in the presence of catalase. In contrast, human glioma cells lacking functional p53, either due to mutation or the expression of E6 protein of human papillomavirus, were highly resistant to etoposide and exhibited no significant change in the ceramide level. Moreover, expression of functional p53 protein in glioma cells expressing mutant p53 using a temperature-sensitive human p53(Val138) induced ceramide accumulation by the activation of neutral sphingomyelinase which was dependent on the generation of O2-*. Taken together, these results suggest that p53 may modulate ceramide generation by activation of neutral sphingomyelinase through the formation of O2-*, but not its downstream compounds H2O2 or * OH.

Reduced glutathione (GSH) and N-acetylcysteine (NAC), but not other antioxidative or reducing agents, were found to inhibit cell death, both apoptosis and necrosis, induced by hypoxia in naive and nerve growth factor-differentiated PC12 cells. The level of intracellular total GSH decreased time-dependently during hypoxia, but exogenously added GSH prevented such a decrease in GSH. Pretreatment of cells with exogenous GSH or NAC resulted in inhibition of both neutral sphingomyelinase (SMase) activation and ceramide formation during hypoxia. In the in vitro assay system, neutral SMase activity was inhibited dose-dependently by GSH and NAC. Activation of caspase-3 induced by hypoxia was also inhibited by either GSH or NAC. NAC but not GSH inhibited caspase-3 activation induced by C2-ceramide. These results suggest that GSH protects cells from hypoxic injury by direct inhibition of neutral SMase activity and ceramide formation, resulting in inhibition of caspase-3 activation, and that NAC exerts an additional inhibitory effect(s) downstream of ceramide.

Direct surgery for the aneurysms at the C3 portion of the internal carotid artery (ICA) requires relatively complicated procedures. We present three patients with this aneurysm who underwent endovascular embolization. The remodelling technique was utilized in two of these patients with unruptured aneurysms. Sufficient obliteration was achieved in every case. Endovascular embolization may be an important alternative for ICA C3 aneurysms.

Intracranial hemorrhage is the major catastrophic event in the natural course of Moyamoya disease, and outcome of the patients with rebleeding is very poor. However, the mechanism underlying intracranial rebleeding is not well elucidated. We retrospectively analyzed 15 patients who bled two times or more among 46 bled patients with Moyamoya disease. The results indicated that there were two different types in the manner of rebleeding. One group consisted of seven cases, which bled two times or more at the same site than the original bleeding site. In four of these seven cases, a ruptured aneurysm was identified at the distal part of collateral vessel or on the major vessel. In the other three cases, no source of bleeding was identified. In all of these cases, rebleeding occurred within 2 months after the initial insult except for one case. Another group consisted of eight cases, which bled repeatedly but at different sites from the initial bleeding site. In any of these cases, neither aneurysms nor other vascular abnormalities were identified. In all of these cases, rebleeding occurred more than 2 months after the initial bleeding. The present result indicated that intracranial bleeding might occur as a result of rupture of a tiny aneurysm at the periphery of collateral vessels. These aneurysms may be blown out after initial bleeding. When they persist after the event, they may rupture again in a fairly short interval. In other cases, bleeding occur at different sites from the initial site. They are considered to be a result of ruptured weak Moyamoya vessels which are forced to act as collateral pathways and are under unusually increased hemodynamic stress.

We evaluated the effect of intra-arterially infused papaverine solutions of various concentrations on cerebral vasospasm following subarachnoid haemorrhage. A total of 90 vascular territories in 46 patients with symptomatic cerebral vasospasm after subarachnoid haemorrhage were treated with intra-arterial infusions of papaverine. In all patients, papaverine was infused at the top of the internal carotid artery (ICA). Of the 90 vascular territories, 30 vascular territories in 14 patients were treated with an infusion of 0.1-0.2% (weight/volume) papaverine (Group 1), 30 vascular territories in 16 patients were treated with a 0.4% (w/v) papaverine infusion (Group 2), and 30 vascular territories in 16 patients were treated with an infusion of 0.8-2.0% (w/v) papaverine (Group 3). Among the three groups, we compared the vasodilatory effects of papaverine by assessing the angiographical and clinical improvements following the treatment. When 0.4% (w/v) papaverine was infused, 24 vascular territories (80%) were successfully dilated and 7 patients (44%) showed a marked reversal of neurological deficits due to vasospasm. Therefore, 80 mg/20 ml (0.4% (w/v)) papaverine infused over a 10-minute period proved to be a beneficial concentration. Transient focal neurological deficits due to the infusion of papaverine occurred in 1 Group 1 patient (7%), 1 Group 2 patient (6%), and 7 Group 3 patients (44%). Highly concentrated papaverine had a higher risk of temporary deterioration. In conclusion, the papaverine concentration of 0.4% (w/v) infused at the top of the ICA was a safe and adequate concentration for treating cerebral vasospasm.

A total of 34 stenotic lesions of the vertebral or subclavian artery were treated in 29 patients using percutaneous transluminal angioplasty (PTA). Seventeen patients were followed angiographically for up to 2 years after PTA. Of 17 patients, five (29.4%) had restenosis which developed between 3 and 6 months after the procedure. Of these patients, two were treated by repeat angioplasty uneventfully, two were treated by surgical reconstruction, and the fifth is being observed without treatment while the patient remains asymptomatic. Neointimal fibromuscular hyperplasia as seen in the surgically resected specimens was thought to be the major cause of restenosis after PTA. Indications of PTA for vertebrobasilar and subclavian artery restenosis are discussed.