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Mutations in optineurin(OPTN) have been identified in a small proportion of sporadic and familial amyotrophic lateral sclerosis (ALS) cases. Recent evidences suggest that OPTN would be involved in not only the pathophysiological mechanisms of motor neuron death of ALS but also myofiber degeneration of sporadic inclusion body myositis. However, the detailed role of OPTN in muscle remains unclear. Initially, we showed that OPTN expression levels were significantly increased in the denervated muscles of mice, suggesting that OPTN may be involved in muscle homeostasis. To reveal the molecular role of OPTN in muscle atrophy, we used cultured C2C12 myotubes treated with tumor necrosis factor-like inducer of apoptosis (TWEAK) as an in vitromodel of muscle atrophy. Our data showed that OPTN had no effect on the process of muscle atrophy in this model. On the other hand, we found that myogenic differentiation was affected by OPTN. Immunoblotting analysis showed that OPTN protein levels gradually decreased during C2C12 differentiation. Furthermore, OPTN knockdown inhibited C2C12 differentiation, accompanied by reduction of mRNA and protein expression levels of myogenin and MyoD. These findings suggested that OPTN may have a novel function in muscle homeostasis and play a role in the pathogenesis of neuromuscular diseases.

Exposure of proteins to reducing sugars results in nonenzymatic glycation with the ultimate formation of advanced glycation end products (AGEs). One means through which AGEs modulate cellular functions is through [...]

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IMPORTANCE: The Systolic Blood Pressure Intervention Trial (SPRINT) demonstrated that a systolic blood pressure (BP) target less than 120 mm Hg was superior to less than 140 mm Hg for preventing vascular events. This trial excluded patients with prior stroke; therefore, the ideal BP target for secondary stroke prevention remains unknown. OBJECTIVE: To assess whether intensive BP control would achieve fewer recurrent strokes vs standard BP control. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial (RCT) of standard vs intensive BP control in an intent-to-treat population of patients who had a history of stroke. Patients were enrolled between October 20, 2010, and December 7, 2016. For an updated meta-analysis, PubMed and the Cochrane Central Library database were searched through September 30, 2018, using the Medical Subject Headings and relevant search terms for cerebrovascular disease and for intensive BP lowering. This was a multicenter trial that included 140 hospitals in Japan; 1514 patients who had a history of stroke within the previous 3 years were approached, but 234 refused to give informed consent. INTERVENTIONS: In total, 1280 patients were randomized 1:1 to BP control to less than 140/90 mm Hg (standard treatment) (n = 640) or to less than 120/80 mm Hg (intensive treatment) (n = 640). However, 17 patients never received intervention; therefore, 1263 patients assigned to standard treatment (n = 630) or intensive treatment (n = 633) were analyzed. MAIN OUTCOMES AND MEASURES: The primary outcome was stroke recurrence. RESULTS: The trial was stopped early. Among 1263 analyzed patients (mean [SD] age, 67.2 [8.8] years; 69.4% male), 1257 of 1263 (99.5%) completed a mean (SD) of 3.9 (1.5) years of follow-up. The mean BP at baseline was 145.4/83.6 mm Hg. Throughout the overall follow-up period, the mean BP was 133.2/77.7 (95% CI, 132.5-133.8/77.1-78.4) mm Hg in the standard group and 126.7/77.4 (95% CI, 125.9-127.2/73.8-75.0) mm Hg in the intensive group. Ninety-one first recurrent strokes occurred. Nonsignificant rate reductions were seen for recurrent stroke in the intensive group compared with the standard group (hazard ratio [HR], 0.73; 95% CI, 0.49-1.11; P = .15). When this finding was pooled in 3 previous relevant RCTs in a meta-analysis, the risk ratio favored intensive BP control (relative risk, 0.78; 95% CI, 0.64-0.96; P = .02; absolute risk difference, −1.5%; 95% CI, −2.6% to −0.4%; number needed to treat, 67; 95% CI, 39-250). CONCLUSIONS AND RELEVANCE: Intensive BP lowering tended to reduce stroke recurrence. The updated meta-analysis supports a target BP less than 130/80 mm Hg in secondary stroke prevention. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01198496

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Tau deposits have distinct biochemical characteristics and vary morphologically based on identification with tau antibodies and several chemical dyes. Here, we report 4′,6-diamidino-2-phenylindole (DAPI)-positivity of tau deposits. Furthermore, we investigated the cause for this positivity. DAPI was positive in 3R/4R (3-repeat/4-repeat) tau deposits in Alzheimer’s disease, myotonic dystrophy, and neurodegeneration with brain iron accumulation, and in 4R tau deposits in corticobasal degeneration, but negative in 4R tau deposits in frontotemporal dementia with parkinsonism-17 and progressive supranuclear palsy. The peak emission wavelength of DAPI after binding to a tau deposit was similar to that after binding to a nucleus. This DAPI-positivity was conspicuous at the optimum concentration of 2 μg/ml. DAPI-positivity was diminished after formic acid treatment, but preserved after nucleic acid elimination and phosphate moiety blocking. Our results suggest that staining with 2 μg/ml DAPI is a common but useful tool to differentially detect tau deposits in various tauopathies.

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ABSTRACTBackground: This comparison of PRAsugrel and clopidogrel in Japanese patients with ischemic STROke (PRASTRO)-I trial investigates the noninferiority of prasugrel to clopidogrel sulfate in the prevention of recurrence of primary events (ischemic stroke, myocardial infarction, and death from other vascular causes), and the long-term safety of prasugrel in Japanese patients with non-cardioembolic stroke.Research design and methods: This was an active-controlled, randomized, double-blind, double-dummy, parallel-group study conducted between July 2011 and March 2016 at multiple centers around Japan. Patients had to meet eligibility criteria before receiving 3.75 mg prasugrel or 75 mg clopidogrel orally once daily for a period of 96–104 weeks.Results: A total of 3747 patients were included in this trial; 1598 in the 3.75 mg prasugrel group and 1551 in the 75 mg clopidogrel group completed the study. During the study period, 287 (15.2%) patients in the prasugrel group and 311 (16.7%) in the clopidogrel group discontinued treatment. Baseline characteristics, safety, and efficacy results are forthcoming and will be published separately.Conclusions: This article presents the study design and rationale for a trial investigating the noninferiority of prasugrel to clopidogrel sulfate with regards to the inhibitory effect on primary events in patients with non-cardioembolic stroke.

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In addition to centrally regulating electrolyte homeostasis and blood pressure, angiotensin IIhas various general effects on the central nervous system. The existence of renin-angiotensin system components in the brain has been well established. Angiotensin II and other renin-angiotensin system components are synthesized and distributed throughout the brain. Post-ischemic oral administration of a non-hypotensive dose (1/10th of the clinical dose) of angiotensin receptor blocker (ARB) has protective effects on reducing cerebral ischemic injury and improving neurological outcomes. Brain tissue angiotensin II levels transiently increase after reperfusion through the local generation of angiotensin IIand not via the transudation of plasma angiotensin II. Systemic administration of ARBs decreases brain tissue angiotensin II in both the intact and ischemic brain tissue via downregulation of angiotensinogen and angiotensin-converting enzyme mRNA expression, although plasma ARB barely crosses the blood-brain barrier during systemic ARB treatment. Only hypotensive dose of ARB treatment opens leptomeningeal anastomoses. Therefore, systemic ARB treatment shows neuroprotective effects not through increasing collateral perfusion but decreasing brain tissue angiotensin II in a nonhypotensive dose.

In addition to senile plaque and neurofibrillary tangles, granulovacuolar degeneration is a hallmark of Alzheimer’s disease. A number of tau kinases, such as c-jun N-terminal kinase (JNK), glycogen-synthase kinase-3 (GSK3), and casein kinase 1 (CK1), have been reported to be markers of granulovacuolar degeneration. In addition, cyclin-dependent kinase 5 (CDK5), which phosphorylates tau, has been shown to be abundantly expressed in neurofibrillary tangles in the hippocampus. CDK5 has a unique staining pattern, and therefore, has the potential to be a novel marker for granulovacuolar degeneration. In this study, we investigated the ability of CDK5 to be a marker for granulovacuolar degeneration using immunohistochemical analysis. Four Alzheimer’s disease cases, three myotonic dystrophy (MyD) cases, and three control cases were subjected to immunohistochemistry and immunofluorescent techniques using anti-CDK5, anti-charged multivesicular body protein 2B (CHMP2B), anti-pSmad23, anti-ubiquitin (Ub), anti-phospho-TDP-43 and AT8 antibodies. Some CDK5-positive granules were morphologically similar to granulovacuolar degeneration intraluminal granules, and these granules overlapped with those immunopositive for pSmad23, Ub and phospho-TDP-43 established granulovacuolar degeneration markers. Moreover, CDK5-positive granulovacuolar degeneration and phosphorylated tau colocalized in pyramidal neurons in Alzheimer’s disease and MyD cases. The numbers of CDK5-positive granules showed an inverse relationship with the degree of mature neurofibrillary tangles in each cell, as was the case with CHMP2B-positive granulovacuolar degeneration granules and neurofibrillary tangles. The presence of tau kinases including CDK5 in granulovacuolar degeneration might implicate that granulovacuolar degeneration is structurally involved in tau modification.

Neurovascular protection against cerebral ischemia is not consistently observed with a postischemia hypotensive dose of candesartan. The aim of this study was to determine the levels of brain angiotensin II after reperfusion and the efficacy and therapeutic time window of postischemic treatments with hypotensive doses of candesartan for the treatment of cerebral ischemia.

We used electric median nerve stimuli to elucidate the functional properties of neurons in the human secondary somatosensory cortex during exploration of small objects and muscle contraction. Somatosensory evoked fields were recorded from nine healthy subjects with a 204-channel neuromagnetometer. Electrical stimuli were applied once every 3 s to the left median nerve at the wrist. The conditions during the stimulation were rest (control session), exploration of small objects (exploration session) and clenching the hand while the wrist was being electrically stimulated (clench session). The strengths of equivalent current dipoles of evoked fields from the secondary somatosensory cortex were increased during the exploration session, but those of evoked fields were decreased by the clench session.

The relationship between levels of circulating intercellular cell-adhesion molecule-1 (cICAM-1) or P-selectin (cP-selectin) and the severity of carotid atherosclerosis was examined in 301 outpatients undergoing duplex ultrasonographic examination. Carotid plaque was defined as an intima-media thickness greater than 1.0 mm, and a plaque score (PS) was calculated from the plaque thickness in both carotid arteries. Multivariate analysis demonstrated significant positive associations between cICAM-1 and the number of plaques [β = 0.11; confidence interval (CI), 0.007–0.213], maximum intima-media thickness (β = 0.11; CI, 0.01–0.219), and PS (β = 0.10; CI, 0.001–0.205). In contrast, no significant association was found for cP-selectin. cP-selectin did not increase until atherosclerosis was advanced (PS > 10), showing a marked increase in patients with ≥ 50% stenosis. The circulating levels of both proteins are related to real measurements of plaque formation in the carotid arteries independently of classical risk factors. Marked elevation of cP-selectin occurs in advanced carotid atherosclerosis after gradual elevation of cICAM-1.

Apolipoprotein E (APOE) deficiency has been shown to worsen neuronal injuries after cerebral ischemia. However, the molecular mechanism underlying the protective effect of APOE remains uncertain, even though several mechanisms including excitotoxicity, free radicals, and apoptosis have been cited as causes of selective neuronal vulnerability in cerebral ischemia. In the present study, we compared the vulnerability of cultured neurons prepared from APOE-knockout mice upon exposure to glutamate, hydrogen peroxide, and staurosporine. No significant difference in cell viability was observed after exposure to glutamate or staurosporine between APOE-deficient and wild-type mice. However, exposure to hydrogen peroxide significantly increased the level of cell death in APOE-deficient mice compared with that in wild-type mice. In the adult mice, after transient forebrain ischemia for 12 min, APOE-deficient mice showed more neuronal death than wild-type mice. Pretreatment of APOE-deficient mice with vitamin E for 2 months markedly reduced neuronal death caused by ischemia. The results suggested that APOE exerted the neuroprotective effect against ischemia through its antioxidant action, but not through mitigation of glutamate toxicity or blocking of apoptosis.

Somatosensory evoked fields were recorded to determine the effects of movement and attention on high-frequency oscillations during active finger movements of the ipsilateral and contralateral sides in response to electrical stimulation of the median nerve. A whole-scalp neuromagnetometer was used to record somatosensory evoked fields from eight subjects following electric median nerve stimulation at the wrist. The following three sessions were performed (1) rest, (2) movement of fingers on the ipsilateral in response to stimulation and (3) movement of fingers on the contralateral in response to stimulation. The somatosensory evoked fields with a wide-bandpass (0.1–1000 Hz) were recorded. High-frequency oscillations and N20m were separated by subsequent high-pass (> 300 Hz) and low-pass (< 300 Hz) filtering. The maximum amplitude of high-frequency oscillations decreased during finger movements accompanying a decrease in somatosensory N20m dipole strength. Activation of the motor cortex appeared to suppress both the amplitude of high-frequency oscillations and the N20m dipole strength.

Cerebral blood flow (CBF) can be quantified noninvasively using the brain perfusion index (BPI), determined from radionuclide angiographic data generated with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO). Previously, the BPI has been calculated using graphical analysis (GA); however, the GA method is greatly affected by the first-pass extraction fraction and retention fraction, which are not only variable, but lower in cases with an increased CBF, such as after the administration of acetazolamide. Thus, GA-calculated BPI values (BPIG) may not reflect the absolute CBF. The objective of this study was to use the spectral analysis of radionuclide angiographic data collected using 99mTc-HMPAO to examine changes in the BPI after the administration of acetazolamide. We studied the CBF of both cerebral hemispheres in six healthy male volunteers; the BPI was measured at rest and after the intravenous administration of 1 g of acetazolamide. In all participants, an H215O positron emission tomography (PET) examination was also performed, and the spectral analysis—calculated BPI values (BPIS) and BPIGvalues were compared with the actual CBF measured using H215O PET (mCBFPET). The BPISwas 1.070 ± 0.051 (mean ± SD) at rest and 1.497 ± 0.098 after acetazolamide; the corresponding BPIGvalues were 0.646 ± 0.073 and 0.721 ± 0.107. The BPISvalues were significantly correlated with the mCBFPETvalues, whereas the BPIGvalues were not. According to the BPISvalues, the increase in BPI after the intravenous administration of acetazolamide was 40.1 ± 8.4%, as opposed to an increase of only 11.3 ± 6.5% according to the BPIGvalues. These results suggest that the spectral analysis of 99mTc-HMPAO—generated data yields a more reliable BPI than GA for the quantification of CBF after acetazolamide administration.

Recent studies demonstrated that neurogenesis in the adult hippocampus increased after transient global ischemia; however, the molecular mechanism underlying increased neurogenesis after ischemia remains unclear. The finding that proliferation of progenitor cells occurred at least a week after ischemic insult suggests that the stimulus was not an ischemic insult to progenitor cells. To clarify whether focal ischemia increases the rate of neurogenesis in the remote area, the authors examined the contralateral hemisphere in rats subjected to permanent occlusion of the middle cerebral artery. In the subgranular zone of the hippocampal dentate gyrus, the numbers of bromodeoxyuridine (BrdU)-positive cells increased approximately sixfold 7 days after ischemia. In double immunofluorescence staining, more than 80% of newborn cells expressed Musashi1, a marker of neural stem/progenitor cells, but only approximately 10% of BrdU-positive cells expressed glial fibrillary acidic protein (GFAP), a marker of astrocytes. The number of BrdU-positive cells markedly decreased 28 days after BrdU administration after ischemia, but it was still elevated compared with that of sham-operated rats. In double immunofluorescence staining, 80% of newborn cells expressed NeuN, a marker of differentiated neurons, and 10% of BrdU-positive cells expressed GFAP. However, in the other areas of the contralateral hemisphere including the rostral subventricular zone, the number of BrdU-positive cells remained unchanged. These results showed that focal ischemia stimulated the proliferation of neuronal progenitor cells, but did not support survival of newborn cells in the contralateral hippocampus.

Clearance of infarct tissue would be an important process for tissue repair after a stroke. Delayed clearance may hamper reconstitution of the blood–brain barrier and glial boundary formation. Recent growing evidence has indicated that apolipoprotein E (APOE), a major apoprotein, plays an important role in lipid transport and homeostasis in the brain. The tissue in the infarction contains abundant lipids must be removed for tissue clearance. In the current study, the authors investigated APOE expression after focal ischemia and the functional role of APOE in tissue clearance using APOE-knockout mice. Expression of APOE was delayed, but marked, in immunohistochemistry and immunoblotting 7 days after permanent focal ischemia. Macrophages were found to express APOE in the infarct center. Infarct size was similar after focal ischemia between wild-type and APOE-knockout mice, although there was no APOE protein expression in knockout mice. However, clearance of infarct tissue 2 weeks after ischemia was significantly delayed in APOE-knockout mice compared with wild-type mice. The current study supports current thinking that APOE is a key molecule for tissue remodeling in the brain. Clearance of damaged tissue may be one of the important functions of APOE in the brain.

Recently, the authors isolated a novel gene of the HSP110 family, ischemia responsive protein 94 kDa (irp94), and demonstrated the expression of this gene after transient forebrain ischemia. In the current study, the authors investigated the expression profiles of all HSP110 family members including hsp110/105 and osp94/apg-1, after transient forebrain ischemia using rat four-vessel occlusion model. Among three members of the HSP110 family, induction of hsp110/105 was the most prominent after ischemia. hsp110/105 mRNA expression was clearly enhanced from 4 to 24 hours after a 6-minute or longer ischemic period. First, hsp110/105 mRNA expression was induced in the dentate gyrus, and later in the pyramidal layer. HSP110/105 protein expression also was enhanced by a 6-minute or longer period of ischemia. Profiles of HSP110/105 expression after ischemia were similar to those of inducible HSP70. After transient forebrain ischemia for 10 minutes, HSP110/105 protein was induced in the dentate gyrus and the CA3 pyramidal layer, but not in the CA1 pyramidal neurons. However, 6 minutes of ischemia induced the HSP110/105 protein, as well as the HSP70 protein, in the CA1 region. CA1 pyramidal neurons expressing HSP110/105 acquired tolerance against subsequent severe ischemia. In conclusion, HSP110/105 showed the most prominent induction after ischemia among the three HSP110 gene family members. Colocalization of HSP110/105 and HSP70 in the CA1 neurons that acquired tolerance suggested that induced HSP110/105 might contribute to ischemic tolerance together with HSP70.

The Notch3 gene has been recently identified as a causative gene for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). To investigate the genetic contribution of Notch mutations in familial cases with vascular leukoencephalopathy, we screened 13 patients from 11 unrelated families, which were selected on the basis of magnetic resonance imaging findings and positive family history. We identified three different missense mutations in 5 patients from 4 families. Two (Arg90Cys and Arg133Cys) are the same as previously reported in Caucasian patients, the other (Cys174Phe) is a novel mutation causing a loss of a cysteine in epidermal-growth-factor-like repeats of Notch3. These data indicate that the CADASIL Notch3 mutations were found in approximately 35% of familial cases with leukoencephalopathy, suggesting genetic heterogeneity of the disease.

Recent evidence has shown crucial roles for cell-adhesion molecules in inflammation-induced rolling, adhesion, and accumulation of neutrophils in tissue. Intercellular adhesion molecule-1 (ICAM-1) is one of these adhesion molecules. Previous studies have shown marked reduction in the size of infarction after focal cerebral ischemia by depletion of granulocytes and administration of the antibody against ICAM-1. In the present study we investigated the role of ICAM-1 in the size of ischemic lesions, accumulation of granulocytes, and microcirculatory compromise in focal cerebral ischemia by using ICAM-1–knockout mice. Ischemic lesions were significantly mitigated in knockout mice after permanent and transient focal ischemia, even though the number of granulocytes in the infarcted tissue was almost the same between knockout and wild-type mice. Depletion of granulocytes further decreased the size of ischemic lesions after transient focal ischemia in ICAM-1–knockout mice. Microcirculation was reduced after focal ischemia, but it was better preserved in the cerebral cortex of knockout mice than that of wild-type mice. The present study demonstrated that ICAM-1 played a role in microcirculatory failure and subsequent development and expansion of infarction after focal cerebral ischemia. However, it is highly unlikely that ICAM-1 played a key role in accumulation of granulocytes after focal cerebral ischemia.

We investigated the correlation between N‐acetylaspartate (NAA) level and neuronal density in the hippocampal CA1 region of the brain after occlusion of both common carotid arteries for 5 minutes and reperfusion for 3 hours to 4 weeks in gerbils with and without ischemic preconditioning (tolerance). Animals were divided into four groups—the sham operated group, the nonpreconditioning (non‐p) group, the single‐preconditioning (single‐p) group with 2‐minute ischemia once 2 days before 5‐minute ischemia, and the double‐preconditioning (double‐p) group with 2‐minute ischemia twice 2 days before 5‐minute ischemia (n = 6 for each group). The CA1 region was dissected out from freeze‐dried sections for high‐performance liquid chromatographic assay of NAA, and adjacent sections were stained with cresy1 violet for measurement of the neuronal density. Both NAA (pmol/μg dry weight) and the neuronal density (cells/mm) decreased in the non‐p group after 3 days (NAA = 24.0 ± 3.0; neuronal density = 65 ± 38 cells/mm) and 7 days (NAA = 17.9 ± 2.5; neuronal density = 20 ± 15 cells/mm) and in the single‐p group after 7 days (26.4 ± 3.0, 106 ± 30) compared with the control group (NAA = 32.9 ± 3.0; neuronal density = 203 ± 9 cells/mm). There was no decrease in the double‐p group. The NAA level and the neuronal density showed a good linear correlation. The regional NAA level may be used as an index of neuronal viability.

This study was designed to test the hypothesis that paradoxical embolization would be a cause of embolic strokes and transient ischemic attacks in patients with stroke of uncertain etiology in all age groups.

We have cloned a cDNA encoding the human 150 kDa oxygen-regulated protein (ORP150) from hypoxia-treated astrocytoma U373 cDNA library. The deduced amino acid sequence of 999 residues contains a signal peptide and an ER retention-like signal at the N- and C-termini, respectively. It has a striking sequence similarity (91% identity) with Chinese hamster 170 kDa glucose-regulated protein (GRP170). The N-terminal half of ORP150 exhibits significant similarity to the ATPase domain of HSP70 family proteins with well-conserved ATP binding motifs. Northern blot analysis revealed that induction of ORP150 in U373 cells was not limited to hypoxia but also observed by 2-deoxyglucose or tunicamycin treatment. Furthermore, tissue specificity of expression of ORP150 was quite similar to that of GRP78. These findings suggest that ORP150 participates in quality control of proteins in the ER in response to diverse environmental stresses.

This study was conducted to examine the effect of the intramuscular injection of levallorphan tartrate (1.0 mg), a mixed agonist-antagonist opiate, on the neurological signs, symptoms, and vital signs in 19 patients with acute ischemic stroke. A temporary improvement of hemiplegia or hemiparesis was observed within several minutes after levallorphan injection in 13 of the patients. There were no significant alterations in blood pressure or pulse rate after injection. The findings indicate that levallorphan may have a temporary improving effect on neurological deficits in acute ischemic stroke. In addition, observation of the response to levallorphan may serve to predict the prognosis of the final neurological outcome in this type of patient.

The effects of a very short ischemic insult on hilar somatostatin (SS) neurons were investigated in the gerbil hippocampus by means of immunocytochemistry and in situ hybridization histochemistry. A selective and significant loss of 40% of hilar SS neurons took place after 1 day, and a 60% loss after 7 days following 2 min of ischemia, while no SS neurons were lost during recirculation after 1 min of ischemia. Repeated 2-min periods of ischemia, which induced ischemic tolerance by vulnerable CA1 neurons, caused almost complete loss of hilar SS neurons. This study clearly demonstrates that hilar SS neurons are more vulnerable to ischemic insult than CA1 pyramidal neurons. Ischemic tolerance may be induced during the progressive loss of SS neurons in the hilus by changes in their synaptic connections to CA1 pyramidal neurons.

Abstract: Human platelets were labelled in the absence or presence of plasma using indium-111 labelled oxine sulphate, tropolone or 2-mercaptopyridine-N-oxide (MPO). Under in vitro and in vivo conditions, platelet functions were evaluated by measuring their aggregability, survival, recovery and early distribution. High labelling efficiency was achieved in saline labelling, whereas with plasma labelling, it was necessary to concentrate the platelet-rich plasma to 4.8 × 106 platelets/mgrl. The aggregation of platelets labelled in plasma or saline was compared with that of controls; platelets labelled in saline showed lower aggregability in 2 mgrM ADP but not in 5 mgrM ADP nor with collagen. No significant differences in platelet survival and recovery were noted between platelets labelled in plasma and those labelled in saline. Our results indicate that partial loss of ADP aggregability in vitro does not influence the in vivo viability of platelets labelled in saline. Scintigraphic studies showed that platelets labelled in a saline medium were temporarily sequestrated in the liver but not in the spleen or heart. Thus, platelet labelling in saline does not affect platelet function adversely, but platelets labelled in plasma are more desirable for assessing the early distribution of platelets in the reticuloendothelial system.

We investigated the effect of hyperthermic pretreatment before induction of ischemia using a gerbil model of 5-min forebrain ischemia. A single hyperthermic treatment 18 h before ischemia exhibited a partial protective effect, and repetitive hyperthermic pretreatments at 18-h intervals before ischemia showed clear protection against neuronal death in the CA1 area of the hippocampus, whereas single hyperthermic treatment 3, 6, 24, or 50 h before ischemia exhibited little protective effect. This transient and cumulative neuroprotective effect of hyperthermic pretreatment strongly suggested the involvement of stress reactions after hyperthermia in the protective mechanism against ischemic neuronal death.

To assess whether ischemia could induce GAP-43 mRNA expression, we performed in situ hybridization in gerbil brains that had been subjected to 5 min of global ischemia. In control dentate granule cells, little hybridization was detected in contrast to the intense signal generated by pyramidal neurons of the adult hippocampal formation. After ischemia, we detected a robust GAP-43 signal over hippocampal granule cells at 3 h of reperfusion, persisting through 7 days, and disappearing by 14 days. This demonstrated GAP-43 gene induction after ischemia, and suggests that GAP-43 may be involved in reactive events, including fiber sprouting and synaptic reorganization, that follow ischemia.

Using anti-beta2-adrenoreceptor antibody, we examined immunohistochemically the localization of adrenoreceptor in the rat central nervous system at both lightmicroscopic and electronmicroscopic level. In the areas which are known to be involved in the control of blood pressure, such as the hypothalamus, the nucleus of the solitary tract and the locus coeruleus, there were a number of adrenoreceptor-like immunoreactive (ADR-IR) structures. They were mainly associated with cellular surface of the neuron. However, those localized within the cytoplasm or the nerve fiber were also observed. Immunoelectron microscopic analysis revealed that the ADR-IR structures were associated with post-synaptic density and cytoplasmic organella (endoplasmic reticulum, vesicle). Ultrastructural feature of the ADR-IR fiber was characterized by the synaptic vesicles with immunoreaction products. In addition, we detected that the running pattern of the ADR-IR fibers was often quite similar to that of tyrosine hydroxylase-immunoreactive (i.e. catecholaminergic) fibers. These findings suggest the presence of the presynaptic autoreceptor.In the present study, we have clearly demonstrated the cellular and subcellular localization of adrenoreceptors in the areas related to blood pressure control immunocytochemically. These results suggest the immunocytochemical method should be quite useful for further investigation OF the CNS control of blood pressure.

Younger gerbils have been found to be more resistant than adults to cerebral infarction after carotid ligation. In this study, the perfused cerebral area after bilateral common carotid occlusion was evaluated in infant, young, and adult Mongolian gerbils by the carbon black perfusion method to assess the existence and significance of collateral blood vessels between the vertebrobasilar and carotid circulations. Nineteen gerbils were divided into three groups (i.e., infant, young and adult gerbils aged 3–4, 5–7, and 10–17 weeks, respectively). After bilateral common carotid artery occlusion, carbon black was injected directly into the left ventricle by cardiac puncture through the closed thorax. In five of eight infant gerbils, the whole brain was perfused by carbon black, while in the remaining three, only the cerebellum and brainstem were stained well, and marked bilateral cerebral pallor was observed. On the other hand, carbon black did not perfuse the brain region supplied by the carotid arteries, both in young and adult gerbils (11 animals in total). These results suggest that infant gerbils might have a more highly developed network of collateral blood vessels between the vertebrobasilar and carotid circulations, and the existence of such a significant network might be the basis for the fact that infant gerbils are resistant to cerebral infarction following carotid ligation. We propose that gerbils should be used as a stroke model only when they are 5 weeks old or older.

Cerebral ischemia models using mice have drawn increasing attention, particularly because of the availability of transgenic animals. However, the variability of intracranial vasculature at the circle of Willis in mice can influence the degree of ischemia in both the bilateral common carotid artery (CCA) occlusion and intraluminal suture occlusion models. We have developed a method to predict the extent of the anastomosis between carotid and vertebrobasilar circulation in three mouse strains (C57BL/6, CBA, and DBA/2) by measuring cortical microperfusion with laser Doppler flowmetry during a 1-minute occlusion of both CCA. When animals showed residual cortical microperfusion of less than 12% during bilateral CCA occlusion, the mice showed absence of functional anastomosis, developed ATP depletion in the frontal cortex during occlusion, and had ischemic neuronal death in the hippocampus and caudoputamen after occlusion for 15 minutes and recirculation for 7 days. Furthermore, those mice exhibited decreased local cerebral blood flow and associated ischemic neuronal death in the hippocampus, within the territory supplied by the posterior cerebral artery, with the intraluminal suture occlusion model. The current study demonstrates the need for assessment of intracranial vasculature in each animal by measuring cortical microperfusion during temporary occlusion of both CCA, no matter whether cerebral ischemia is produced by bilateral CCA occlusion or intraluminal suture occlusion in transgenic mice.

To determine whether flushing of the facial skin in response to alcohol consumption (alcohol flushing) is a warning sign of hypertension. We also sought the relationship between alcohol flushing and other risk factors that may contribute to the development of hypertension.

The aim of this study was to elucidate the factors associated with the time from symptom onset to arrival at a stroke center (onset-to-door time ODT) in patients with classically defined transient ischemic attack using data from a multicenter, retrospective study.

This report concerns a 65‐year‐old right‐handed woman with cerebral hemorrhage who presented with mild right‐sided hemiparesis. Computed tomography (CT) revealed hematoma in the left thalamus and compression of the posterior limb of the internal capsule by a brain edema surrounding the lesion. 99mTc‐hexamethylpropyleneamine oxime (HMPAO) single photon emission computed tomography (SPECT) images obtained 4 days after onset showed hypoperfusion in the left thalamus containing a hematoma as well as contralateral cerebellar hypoperfusion to the supratentorial lesion, which is well recognized as crossed cerebellar diaschisis (CCD) after stroke. CT 14 days after the onset revealed reduction of the brain edema of the posterior limb of the internal capsule accompanied by gradual neurological improvement. SPECT obtained 14 and 28 days later showed that CCD had disappeared. In this case report, the authors discuss the disappearance of CCD due to transient edematous compression of the internal capsule following thalamic hemorrhage on serial 99mTc‐HMPAO SPECT scans. CCD was possibly caused by the lesion confined to the posterior limb of the internal capsule, which anatomically constitutes the cerebropontocerebellar pathway.

The presence of immunoreactive glucagon (IRG) in smooth muscle of the cerebral arteries of rats was demonstrated immunohistochemically using two antisera against pancreatic glucagon, OAL-123 and Unger's 30K. Based on the results and on our previous radioimmunoassay and gel filtration study, the smooth muscle cells of the blood vessels may be one of the extrapancreatic sources of IRG in the plasma.

The clinical use of ultrasonic echo Doppler velocimetry as a screening test for renal artery stenosis was investigated in 11 control subjects and 20 hypertensive patients including 10 with renovascular disease. In these hypertensive patients, the accuracy of the diagnosis of renal artery stenosis using the echo Doppler method was compared with that of angiography. The accuracy of the radionuclide renography in the same subjects was also investigated and compared with that of the echo Doppler method. Seven patients with renovascular disease who required angioplasty were examined again after the operation. The duplex Doppler signals were detected through the muscle of the back (the translumbar approach). Diagnosis of renal artery stenosis was based on three objectively defined Doppler parameters, the acceleration index, the acceleration time, and the acceleration: time ratio.

Cerebral air embolism can be easily identified on computed tomography (CT) scans. However, changes in the distribution and amount of intracranial air are not well known. We report two patients with cerebral air embolism and present imaging findings on the serial changes in the intracranial air. We thought that the embolic source was venous in one patient because CT showed air inflow in cortical veins in the bilateral frontal areas, reflecting air buoyancy. In the other patient, CT showed air inflow into not only the cortical veins but also the bilateral cerebral hemispheres and we thought this to be a paradoxical cerebral air embolism. We found that intracranial air can be promptly absorbed and while cerebral infarcts due to air are clearly visualized on diffusion-weighted images (DWI), the air may rapidly disappear from images. In patients with suspected cerebral air embolism whose CT findings show no intracranial air, DWI should be performed because it may reveal cerebral infarction due to cerebral air embolism.

Edoxaban (the free base of DU-176b) is an oral, selective, reversible, direct factor Xa inhibitor in clinical development for the prevention of stroke in patients with non-valvular atrial fibrillation (AF). There is evidence that asymptomatic intracranial hemorrhage (ICH) may be a risk factor for symptomatic ICH in anticoagulated patients. A phase IIb study in Japanese AF patients compared the incidence of asymptomatic ICH with edoxaban and warfarin use.This was a multicenter, randomized, dose comparison study. Patients aged ≥20 years with CHADS2 score ≥1 were randomly assigned to receive 1 of 3 doses of edoxaban (30 mg, 45 mg, or 60 mg QD) or open-label warfarin dose-adjusted to a target international normalized ratio (INR) of 2.0 to 3.0 inclusive for patients aged <70 years and 1.6 to 2.6 inclusive for patients aged ≥70 years, for 12 weeks. The primary objective of the study was to assess the incidence of all bleeding events (major, clinically relevant non-major and minor bleeds) including asymptomatic ICH. Asymptomatic ICH was defined as newly detected hemorrhage on brain image (CT or MRI) by assessing pre- and post-treatment brain images and was obtained from all enrolled patients. All images were assessed by an Asymptomatic ICH Committee that was blinded to treatment assignment.There were no clinically relevant differences in patient demographics and baseline characteristics between treatment groups. Overall, the time within the target INR range was 83% and 73% for patients aged ≥70 years and aged <70 years, respectively. The incidence of all bleeding events increased with increasing doses of edoxaban, but there were no statistically significant differences among the 3 edoxaban groups. The mean (95% confidence interval) incidences of all bleeding for edoxaban 30 mg, 45 mg, and 60 mg, and warfarin were 18.5% (12.7, 26.0), 22.4% (16.2, 30.2), 27.7% (20.7, 35.9), and 20.0% (13.9, 27.9), respectively. Of the total 536 patients enrolled, 17 patients did not fulfill the assessment criteria for asymptomatic ICH. Of the 17 patients, 1 patient in the edoxaban 60-mg group had symptomatic ICH. The remaining 519 (391 edoxaban, 128 warfarin) patients were evaluated for asymptomatic ICH. A total of 431 patients underwent CT (329 edoxaban, 102 warfarin), 81 patients underwent MRI (57 edoxaban, 24 warfarin), and 7 patients underwent CT/MRI (5 edoxaban, 2 warfarin). There were no asymptomatic ICH events in any treatment group. Conclusions: In this study of 3 fixed doses of edoxaban compared with well-controlled warfarin, edoxaban was safe and asymptomatic ICH was not detected.Yasaka: Nippon Boehringer lngelheim Co., Ltd.: Consultancy; Pfizer Japan Inc.: Consultancy; Daiichi Sankyo Co., LTD.: Consultancy. Kawai:Toyama Chemical: Consultancy; DaiichiSankyo: Consultancy. Yamaguchi:Mitsubishi Tanabe Pharma: Consultancy; Otsuka Pharmaceutical: Consultancy. Uchiyama:Bayer Yakuhin, LTD. : Consultancy; Nippon Boehringer lngelheim Co., Ltd.: Consultancy; Astellas Pharma Inc.: Consultancy. Ogawa:TEIJIN PHARMA LIMITED: Consultancy; Pfizer Japan Inc.: Consultancy; Bayer Yakuhin, LTD.: Consultancy; Astellas Pharma : Share Holder; Sanofi-aventis : Paid Instructor. Koretsune:Daiichi Sankyo: Consultancy, National Lead Investigator. Yamashita:Novartis: Consultancy; DaiichiSankyo: Consultancy, National Lead Investigator; Otsuka Pharmaceutical: Paid Instructor; Sanofi-aventis: Paid Instructor; TEIJIN PHARMA: Paid Instructor.

Proteins or lipids exposed to aldose sugars undergo initial and ultimately irreversible modification resulting in the formation of so-called advanced glycation end-products (AGEs). AGEs are postulated to be especially important in the setting of diabetes mellitus due to hyperglycaemia characteristic of this disorder. Our work has demonstrated that one of the principal means by which AGEs interact with the vascular wall is by interaction with their cellular receptor, the receptor for advanced glycation endproducts (RAGE), which is present on the surface of endothelial cells, smooth muscle cells, mesangial cells, mononuclear phagocytes and certain neurons. AGEs interact with RAGE, resulting in the induction of monocyte chemotaxis as well as oxidant stress. One of the consequences of AGE-RAGE-induced cellular oxidant stress is the enhanced expression of vascular cell adhesion molecule-1 on the endothelial surface, a critical consequence of which is the attraction of mononuclear phagocytes into the vessel wall. In both cases, the pro-inflammatory effects of AGEs may be inhibited in the presence of RAGE blockade, using either anti-RAGE F(ab′)2 or soluble RAGE, the extracellular domain of the molecule. These data suggest that inhibition of RAGE may interfere with monocyte chemotaxis and attraction into the vessel wall where AGEs deposit/form, suggesting the potential of this intervention to interfere with a critical step in the development of vascular disease, especially in patients with diabetes.