4-Hydroxyl-2-Nonenal Localized Expression Pattern in Retrieved Clots is Associated with Large Artery Atherosclerosis in Stroke Patients.

OBJECTIVES: The relationship between stroke etiology and clot pathology remains controversial. MATERIALS AND METHODS: We performed histological analysis of clots retrieved from 52 acute ischemic stroke patients using hematoxylin and eosin staining and immunohistochemistry (CD42b and oxidative/hypoxic stress markers). The correlations between clot composition and the stroke etiological group (i.e., cardioembolic, cryptogenic, or large artery atherosclerosis) were assessed. RESULTS: Of the 52 clots analyzed, there were no significant differences in histopathologic composition (e.g., white blood cells, red blood cells, fibrin, and platelets) between the 3 etiological groups (P = .92). By contrast, all large artery atherosclerosis clots showed a localized pattern with the oxidative stress marker 4-hydroxyl-2-nonenal (P < .01). From all 52 clots, 4-hydroxyl-2-nonenal expression patterns were localized in 28.8% of clots, diffuse in 57.7% of clots, and no signal in 13.5% of clots. CONCLUSIONS: A localized pattern of 4-hydroxyl-2-nonenal staining may be a novel and effective marker for large artery atherosclerosis (sensitivity 100%, specificity 82%).

A Patient with a Cavernous Sinus Dural Arteriovenous Fistula in Whom an Approach through the Jugular Venous Arch Involving Facial Vein Return Was Adopted.

Objective: We report the case of a cavernous sinus dural arteriovenous fistula (CSdAVF) treated by transvenous embolization (TVE) via the jugular venous arch (JVA) connecting bilateral superficial cervical veins. Case Presentation: A male patient in his 50s presenting with diplopia and headache was diagnosed with a CSdAVF. The first session of TVE resulted in incomplete obliteration of the fistula due to poor accessibility through the inferior petrosal sinus (IPS), and postoperative computed tomography angiography (CTA) disclosed a newly developed drainage route into the facial vein (FV) connecting to the anterior jugular vein (AJV) and the JVA. The patient underwent the second session of TVE through the JVA, FV, and the superior ophthalmic vein (SOV), and obliteration was achieved. Conclusion: There is a considerable variation in the anatomy of facio-cervical veins in patients with CSdAVF. Meticulous preoperative evaluation of the venous drainage route using modern diagnostic tools is indispensable to achieve successful results in patients with CSdAVF.

Practical Use of a Communication Application on Mobile Devices by Our Stroke Team.

Objective: To describe our 1-year experience of the practical use of a mobile communication application by our stroke team. Methods: The mobile Join application (Allm Inc., Tokyo, Japan) was introduced into our stroke team for the purpose of immediate sharing of the patient information. We analyzed the usage situation for 1 year after the introduction of Join, particularly its efficacy in improving the door-to-puncture time (D2P) for thrombectomy cases, and reported our inter-hospital collaboration with the use of Join. Results: The total number of events notified by Join was 337, and they included acute stroke potentially leading to reperfusion therapy in 23% (76 events), head trauma in 14%, brain hemorrhage in 12%, other infarction in 10%, subarachnoid hemorrhage in 8%, and the others in 34%. The information of the patients was shared among the team members before arrival to our hospital in 42% of acute stroke cases. Of 31 patients undergoing mechanical thrombectomy, the median interval between arrival and groin puncture for the directly transported patients with/without pre-hospital information was 77.5 min/87 min, respectively, whereas that of the patients transferred from primary hospitals with/without pre-hospital information was 19 min/71 min (p <0.0001), respectively, demonstrating the efficacy of information sharing in advance through Join in improving the timing of endovascular therapy. For inter-hospital collaboration using the telestroke system, we concluded the partnership agreement with three local primary hospitals by communication via Join at a reasonable cost. Conclusion: Active and effective utilization of the mobile Join application for communication by our stroke team was demonstrated, and it is expected to promote inter-hospital collaboration in stroke treatment.

Cerebral Infarction Arising from Takotsubo Cardiomyopathy: Case Report and Literature Review.

Although most patients with takotsubo cardiomyopathy have a favorable outcome, complications are not uncommon. Recent studies have reported an increase in incidence of cardioembolic complications; however, the association between takotsubo cardiomyopathy and stroke, in particular thromboembolic cerebral infarction, remains unclear. We reported a 44-year-old woman who had a cerebral infarction resulting from takotsubo cardiomyopathy. She had felt chest discomfort a few days prior to infarction, and later developed left hemiparesis. Head magnetic resonance imaging (MRI) revealed acute infarction in the right insular cortex and occlusion of the right middle cerebral artery at the M2 segment. Echocardiogram revealed a takotsubo-like shape in the motion of the left ventricular wall, and coronary angiography showed neither coronary stenosis nor occlusion. Cerebral infarction resulting from takotsubo cardiomyopathy was diagnosed and treatment with anticoagulant was started. MRI on the eighth day after hospitalization showed recanalization of the right middle cerebral artery and no new ischemic lesions. The findings of the 19 previously published cases who had cerebral infarction resulting from takotsubo cardiomyopathy were also reviewed and showed the median interval between takotsubo cardiomyopathy and cerebral infarction was approximately 1 week and cardiac thrombus was detected in 9 of 19 patients. We revealed that thromboembolic events occurred later than other complications of takotsubo cardiomyopathy and longer observation might be required due to possible cardiogenic cerebral infarction. Anticoagulant therapy is recommended for patients with takotsubo cardiomyopathy with cardiac thrombus or a large area of akinetic left ventricle.

[Multiple brain abscesses in the territory of the vertebral-basilar artery resulting from an infected aortic arch graft].

A 62-year-old man with high fever and in a state of disorientation was transferred to our hospital. One year before this transfer, he had undergone total arch replacement surgery for thoracic aortic dissection. On admission to our hospital, head MRI revealed multiple brain abscesses in the territory of the vertebral-basilar artery, and chest CT showed gas around the aortic graft, in particular, at the origin of the left subclavian artery. We diagnosed him with brain abscesses in the left vertebral-basilar artery resulting from an infected aortic graft. We immediately began administration of intravenous antibiotics. Although his blood, urine, and cerebrospinal fluid cultures were negative, fortunately, the brain abscesses and ectopic gas disappeared. Since reports of only antibiotic use for treating brain abscesses due to aortic graft infection are rare, the appropriate duration of antibiotic administration has not been established yet. Therefore, careful observation is required in this case.

Optimal dose of plasmid vascular endothelial growth factor for enhancement of angiogenesis in the rat brain ischemia model.

Vascular endothelial growth factor (VEGF) administration has recently been assessed as a therapeutic strategy for ischemic diseases including brain ischemia because of its angiogenic effect. However, VEGF also causes detrimental adverse effects by increasing vascular permeability. This study examined whether plasmid human VEGF (phVEGF) administration induced angiogenic effects in the rat brain ischemia model caused by permanent ligation of both common carotid arteries, and investigated the occurrence of adverse effects. Administration of various doses (0-200 microg) of phVEGF in the temporal muscle was followed by encephalo-myo-synangiosis. Thirty days after treatment, the numbers and areas of capillaries per field in the extracted brains were analyzed with the National Institutes of Health Image software program. The maximal angiogenic effect occurred with a 100 microg dose of phVEGF in the numbers and areas of capillaries in the VEGF-treated brains. Histological examination showed no apparent adverse effects in the brain parenchyma even at the highest administration dose (200 microg) of phVEGF. The maximal angiogenic effect at the optimal dose of phVEGF can be considered under the threshold to cause serious adverse effects in the rat brain.

Triple-catheter technique in the transvenous coil embolization of an isolated sinus dural arteriovenous fistula.

OBJECTIVE: Dural arteriovenous fistulae involving the transverse-sigmoid sinus, which is occluded at its proximal and distal ends (i.e., an isolated sinus), carry a high risk of intracranial hemorrhage or progressive neurological deficits. Although transvenous coil embolization is a useful and safe treatment for such lesions, it is often difficult to reach into the isolated sinus through the occluded sinus using the percutaneous catheter approach. METHODS: We report the successful treatment of two patients with transverse-sigmoid dural arteriovenous fistulae with isolated sinus using the percutaneous transvenous triple-catheter technique. A 6-French guiding catheter was placed at the internal jugular vein followed by a second 4-French catheter positioned at the end of the occluded sinus. A third microcatheter was then navigated into the isolated sinus with support of the second catheter. RESULTS: Although initial attempts to reach into the isolated sinus without the second catheter failed, insertion of the second catheter resulted in successful navigation of the third microcatheter into the affected sinus in both cases. Complete cure was obtained in both cases by coil packing of the affected sinus. CONCLUSION: Although careful maneuvering is required, this triple-catheter technique is useful for treatment of dural arteriovenous fistulae with isolated sinus.

Packing efficacy of hydrocoil embolic system: in vitro study using ruptured aneurysm model.

After endovascular coil embolization of cerebral aneurysms, coil compaction and late aneurysm recanalization have been ever observed. The HydroCoil Embolic System (HES) was developed to improve the packing efficacy of endovascular treatment of cerebral aneurysms. In this study, we evaluate the packing efficacy of HES using a silicone model of ruptured cerebral aneurysm. This silicone model was connected to a pulsatile flow pump and embolized with the initial framing coils followed by hydro coils (n = 3) or bare platinum coils (n = 3). The coils used in the two groups were identical to each other in size and length. In the hydro coil group, continuous outflow from ruptured aneurysm ceased in two out of three cases. On the other hand, in the bare platinum coil group, outflow from the ruptured point slightly decreased but did not stop in all cases. The hydro coil could result in a higher initial occlusion rate of silicone model. In addition, expanded hydrogel possibly sealed the ruptured point directly. Changes in the size of aneurysms were not detected, from which the risk of over-expansion seemed extremely low. The hydro Coil is a safe and feasible device for improving the packing efficacy in endovascular coil embolization.

Synthesis and biological activity of 5',9-anhydro-3-purine-isonucleosides as potential anti-hepatitis C virus agents.

In order to study structure-activity relationships among the derivatives and congeners of 5',9-anhydro-3-(beta-D-ribofuranosyl)xanthine for anti-hepatitis C virus activity, a series of 5',9-anhydro-purine-isonucleosides with a substituent (s) at 6- or/and 8-position of the purine moiety were synthesized, and their anti-hepatitis C virus activity and cytotoxicity were evaluated and discussed.

Synthesis and antiviral activity of 2'-deoxy-2'-fluoro-2'-C-methyl purine nucleosides as inhibitors of hepatitis C virus RNA replication.

A series of purine nucleosides containing the 2'-deoxy-2'-fluoro-2'-C-methylribofuranosyl moiety were synthesized and evaluated as potential inhibitors of the hepatitis C virus in vitro. Of the nucleosides that were synthesized, only those possessing a 2-amino group on the purine base reduced the levels of HCV RNA in a subgenomic replicon assay.

N4-hydroxycytosine dioxolane nucleosides and their activity against hepatitis B virus.

Novel racemic, D- and L-beta-dioxolane N4-hydroxycytosine nucleosides have been synthesized and evaluated for their activity against hepatitis B virus. None of the synthesized nucleosides demonstrated selective anti-HBV activity.

Unusual olefin formation by PhSe-F trans-elimination.

A new approach to the synthesis of 2',3'-didehydro-2',3-dideoxynucleosides was described in excellent yield through unusual olefin formation by PhSe-F trans-elimination.

Synthesis and in vitro anti-HCV activity of beta-D- and 1-2'-deoxy-2'-fluororibonucleosides.

Based on the discovery of beta-D-2'-deoxy-2'-fluorocytidine as a potent anti-hepatitis C virus (HCV) agent, a series of beta-D- and L-2'-deoxy-2'-fluoroibonucleosides with modifications at 5 and/or 4 positions were synthesized and evaluated for their in vitro activity against HCV and bovine viral diarrhea virus (BVDV). The introduction of the 2'-fluoro group was achieved by either fluorination of 2,2'-anhydronucleosides with hydrogen fluoride-pyridine or potassium fluoride, or a fluorination of arabinonucleosides with DAST. Among the 27 analogues synthesized, only the 5-fluoro compounds, namely beta-D-2'-deoxy-2',5-difluorocytidine (5), had anti-HCV activity in the subgenomic HCV replicon cell line, and inhibitory activity against ribosomal RNA. As beta-D-N4-hydroxycytidine (NHC) had previously shown potent anti-HCV activity, the two functionalities of the N4-hydroxyl and the 2'-fluoro were combined into one molecule, yielding beta-D-2'-deoxy-2'-fluoro-N4-hydroxycytidine (12). However, this nucleoside showed neither anti-HCV activity nor toxicity. All the L-forms of the analogues were devoid of anti-HCV activity. None of the compounds showed anti-BVDV activity, suggesting that the BVDV system cannot reliably predict anti-HCV activity in vitro.

Synthesis of N3,5'-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridin-5-one and its 3'-deoxysugar analogue as potential anti-hepatitis C virus agents.

We recently discovered a novel compound, identified as N3, 5-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridinin-5-one, with anti-hepatitis C virus (HCV) activity in vitro. The structure was confirmed by chemical synthesis from 2-hydroxy-5-nitropyridine. It showed anti-HCV activity with EC50= 19.7 microM in replicon cells. Its 3'-deoxy sugar analogue was also synthesized, but was inactive against HCV in vitro.

Synthesis and anti-hepatitis C virus activity of nucleoside derivatives of N3, 5'-anhydro-4-(beta-D-ribofuranosyl)-8-aza-purin-2-ones.

A series of N3, 5-Anhydro-4-(beta-D-ribofuranosyl)-8-azapurin-2-ones were prepared in multistep reactions from uridine as potential anti-hepatitis C virus (HCV) agents. The synthetic details as well as biological evaluations are discussed.

Synthesis and structure-activity relationships of novel anti-hepatitis C agents: N3,5'-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridin-5-one derivatives.

Several 6- and 7-monosubstituted N3,5'-cyclo-4-(beta-d-ribofuranosyl)-vic-triazolo[4,5-b]pyridin-5-one derivatives as well as the 5-thiono analogue were synthesized, providing structure-anti-hepatitis C virus (HCV) activity relationships for the series. Among the compounds synthesized, the 6-bromo, 7-methylamino, and 5-thiono analogues exhibited more potent anti-HCV activity in an HCV subgenomic replicon cell based assay (EC90 = 1.9, 7.4, and 10.0 microM, respectively) than the lead compound N3,5'-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridin-5-one (EC90 = 79.8 microM).

Design, synthesis, and antiviral activity of 2'-deoxy-2'-fluoro-2'-C-methylcytidine, a potent inhibitor of hepatitis C virus replication.

The pyrimidine nucleoside beta-d-2'-deoxy-2'-fluoro-2'-C-methylcytidine (1) was designed as a hepatitis C virus RNA-dependent RNA polymerase (HCV RdRp) inhibitor. The title compound was obtained by a DAST fluorination of N(4)-benzoyl-1-(2-methyl-3,5-di-O-benzoyl-beta-d-arabinofuranosyl]cytosine to provide N(4)-benzoyl-1-[2-fluoro-2-methyl-3,5-di-O-benzoyl-beta-d-ribofuranosyl]cytosine. The protected 2'-C-methylcytidine was obtained as a byproduct from the DAST fluorination and allowed for the preparation of two biologically active compounds from a common precursor. Compound 1 and 2'-C-methylcytidine were assayed in a subgenomic HCV replicon assay system and found to be potent and selective inhibitors of HCV replication. Compound 1 shows increased inhibitory activity in the HCV replicon assay compared to 2'-C-methylcytidine and low cellular toxicity.

Synthesis and anti-viral activity of a series of d- and l-2'-deoxy-2'-fluororibonucleosides in the subgenomic HCV replicon system.

Based on the discovery of (2'R)-d-2'-deoxy-2'-fluorocytidine as a potent anti-hepatitis C virus (HCV) agent, a series of d- and l-2'-deoxy-2'-fluororibonucleosides with modifications at 5- and/or 4-positions were synthesized and evaluated for their in vitro activity against HCV and bovine viral diarrhea virus (BVDV). The key step in the synthesis, the introduction of 2'-fluoro group, was achieved by either fluorination of 2,2'-anhydronucleosides with hydrogen fluoride-pyridine or potassium fluoride, or a fluorination of arabinonucleosides with DAST. Among the 27 analogues synthesized, only the 5-fluoro compound, namely (2'R)-d-2'-deoxy-2',5-difluorocytidine (13), demonstrated potent anti-HCV activity and toxicity to ribosomal RNA. The replacement of the 4-amino group with a thiol group resulted in the loss of activity, while the 4-methylthio substituted analogue (25) exhibited inhibition of ribosomal RNA. As N(4)-hydroxycytidine (NHC) had previously shown potent anti-HCV activity, we combined the two functionalities of the N(4)-hydroxyl and the 2'-fluoro into one molecule, resulting (2'R)-d-2'-deoxy-2'-fluoro-N(4)-hydroxycytidine (23). However, this nucleoside showed neither anti-HCV activity nor toxicity. All the l-forms of the analogues were devoid of anti-HCV activity. None of the compounds showed anti-BVDV activity, suggesting that the BVDV system cannot always predict anti-HCV activity.

Synthesis and anti-HCV activity of N9,5'-cyclo-3-(beta-D-ribofuranosyl)-8-azapurin-2-one derivatives.

A number of 1- or 6-substituted N9,5'-cyclo-3-(beta-ribofuranosyl)-8-azapurin-2-one derivatives were synthesized in multi-step reactions. Their anti-hepatitis C virus activities were evaluated and some structure-activity relationship is discussed.

Synthesis of N3,5'-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridin-5-one, a novel compound with anti-hepatitis C virus activity.

A novel anti-hepatitis C virus (HCV) agent, N(3),5'-cyclo-4-(beta-D-ribofuranosyl)-vic-triazolo[4,5-b]pyridinin-5-one, was identified, and the structure was confirmed by chemical synthesis from 2-hydroxy-5-nitropyridine.