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The transcranial Doppler method (TCD) enables the measurement of cerebral blood flow velocity and detection of emboli by applying an ultrasound probe to the temporal bone window, or the orbital or greater occipital foramina. TCD is widely used for evaluation of cerebral vasospasm after subarachnoid hemorrhage, early detection of patients with arterial stenosis, and the assessment of brain death. However, measurements often become difficult in older women. Among various factors contributing to this problem, we focused on the effect of the diploe in the skull bone on the penetration of ultrasound into the brain. In particular, the effect of the cancellous bone structure in the diploe was investigated. Using a 2D digital bone model, wave propagation through the skull bone was investigated using the finite-difference time-domain (FDTD) method. We fabricated digital bone models with similar structure but different BV/TV (bone volume/total volume) values in the diploe. At a BV/TV of approximately 50-60% (similar to that of older women), the minimum ultrasound amplitude was observed as a result of scattering and multiple reflections in the cancellous diploe. These results suggest that structural changes such as osteoporosis may be one factor hampering TCD measurements., (© 2021. The Author(s).)

Drastic sensitivity enhancement of dynamic nuclear polarization is becoming an increasingly critical methodology to monitor real-time metabolic and physiological information in chemistry, biochemistry, and biomedicine. However, the limited number of available hyperpolarized 13 C probes, which can effectively interrogate crucial metabolic activities, remains one of the major bottlenecks in this growing field. Here, we demonstrate [1- 13 C] N-acetyl cysteine (NAC) as a novel probe for hyperpolarized 13 C MRI to monitor glutathione redox chemistry, which plays a central part of metabolic chemistry and strongly influences various therapies. NAC forms a disulfide bond in the presence of reduced glutathione, which generates a spectroscopically detectable product that is separated from the main peak by a 1.5 ppm shift. In vivo hyperpolarized MRI in mice revealed that NAC was broadly distributed throughout the body including the brain. Its biochemical transformation in two human pancreatic tumor cells in vitro and as xenografts differed depending on the individual cellular biochemical profile and microenvironment in vivo. Hyperpolarized NAC can be a promising non-invasive biomarker to monitor in vivo redox status and can be potentially translatable to clinical diagnosis.

Deleterious mutations in patchd1 domain containing 1 (PTCHD1) gene have been identified in patients with intellectual disability and/or autism spectrum disorder (ASD). To clarify the causal relationship between Ptchd1 deficiency and behavioral defects relevant to neurodevelopmental disorders, we generated global Ptchd1 knockout (KO) mice. Ptchd1 KO mice displayed hyperlocomotion, increased impulsivity, and lower recognition memory, which resemble attention-deficit hyperactivity disorder (ADHD)-like behaviors. Acute or chronic treatment with atomoxetine ameliorated almost all behavioral deficits in Pthcd1 KO mice. We next determined possible involvement of the kynurenine pathway (KP) metabolites in neurodevelopmental disorders in Ptchd1 KO mice and assessed the potential of KP metabolites as biomarkers for ADHD and/or ASD. Ptchd1 KO mice showed drastic changes in KP metabolite concentrations in the serum and the brain, indicating that the activated KP is associated with ADHD-like behaviors. Our findings indicate that Ptchd1 KO mice can be used as an animal model of human ADHD and/or ASD, and KP metabolites are potential diagnostic biomarkers for neurodevelopmental disorders.

There is a great deal of individual variability in outcome in second language learning, the sources of which are still poorly understood. We hypothesized that individual differences in auditory processing may account for some variability in second language learning. We tested this hypothesis by examining psychoacoustic thresholds, auditory-motor temporal integration, and auditory neural encoding in adult native Polish speakers living in the UK. We found that precise English vowel perception and accurate English grammatical judgment were linked to lower psychoacoustic thresholds, better auditory-motor integration, and more consistent frequency-following responses to sound. Psychoacoustic thresholds and neural sound encoding explained independent variance in vowel perception, suggesting that they are dissociable indexes of sound processing. These results suggest that individual differences in second language acquisition success stem at least in part from domain-general difficulties with auditory perception, and that auditory training could help facilitate language learning in some individuals with specific auditory impairments., (Copyright © 2019 Elsevier Inc. All rights reserved.)

We herein report a 67-year-old female who presented with progressive dementia and disturbance of consciousness. Brain CT showed multiple subcortical calcifications with edema. Enhanced CT showed multiple abnormal vessels in the left hemisphere. Electroencephalography indicated diffuse spike and slow wave complex, so non-convulsive status epilepticus was diagnosed. Cerebral angiography revealed several feeder arteries with retrograde leptomeningeal venous drainage. We diagnosed her with Borden type III cerebral dural arteriovenous fistulas. Trans-arterial embolization with n-butyl-2-cyanoacrylate was performed, and she has experienced no epileptic attacks for at least ten months. Calcification changes are sometimes seen in Borden type II dural arteriovenous fistulas but not in aggressive types, such as Borden type III. It is important to suspect dural arteriovenous fistulas when we encounter patients with progressive dementia or/and epilepsy with cerebral calcification lesions, as this may be a treatable disease condition.

Background: Wearable devices with heads-up displays or smart glasses can overlay images onto the sight of the wearer. This technology has never been applied to surgical navigation., Objective: To assess the applicability and accuracy of smart glasses for augmented reality (AR)-based neurosurgical navigation., Methods: Smart glasses were applied to AR-based neurosurgical navigation. Three-dimensional computer graphics were created based on preoperative magnetic resonance images and visualized in see-through smart glasses. Optical markers were attached to the smart glasses and the patient's head for accurate navigation. Two motion capture cameras were used for registration and continuous monitoring of the location of the smart glasses in relation to the patient's head. After the accuracy was assessed with a phantom, this technique was applied in 2 patients with brain tumors located in the brain surface., Results: A stereoscopic view by image overlay through the smart glasses was successful in the phantom and in both patients. Hands-free neuronavigation inside the operative field was available from any angles and distances. The targeting error in the phantom measured in 75 points ranged from 0.2 to 8.1 mm (mean 3.1 ± 1.9 mm, median 2.7 mm). The intraoperative targeting error between the visualized and real locations in the 2 patients (measured in 40 points) ranged from 0.6 to 4.9 mm (mean 2.1 ± 1.1 mm, median 1.8 mm)., Conclusion: Smart glasses enabled AR-based neurosurgical navigation in a hands-free fashion. Stereoscopic computer graphics of targeted brain tumors corresponding to the surgical field were clearly visualized during surgery.

Background: Brain involvement of hepatosplenic T cell lymphoma (HSTL) has not been reported so far., Case Description: We observed an extremely rare case of HSTL, which is a rare and aggressive variant of peripheral T cell lymphoma, generally showing predominant infiltration to the liver, spleen, and bone marrow and involving the brain. A 41-year-old Japanese woman presented with dysarthria and numbness of the right hand. Radiologic examination revealed a single 3-cm mass in the left frontal cortex, which was totally removed. Pathologic examination of the specimen demonstrated T cell lymphoma with a γδ cytotoxic T cell phenotype. Multiplex polymerase chain reaction analyses confirmed monoclonality of T cell receptor γ. Systemic examination revealed infiltration of atypical T lymphoid cells of the same phenotype in bone marrow and the presence of hepatosplenomegaly. We diagnosed HSTL involving the brain. The patient was treated with several courses of intensive chemotherapy, but it failed to achieve remission. She died of sepsis 4 months after the surgery., Conclusions: HSTL can involve the brain. A diagnosis of HSTL involving the brain needs careful systemic evaluation. Timely and precise diagnosis that considers the systemic condition is important for appropriate treatment and better outcome., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Idiopathic normal pressure hydrocephalus (iNPH) is a dementia-inducing disorder. Primary cause of iNPH is speculated to be a reduction of cerebrospinal fluid (CSF) absorption, which secondarily induces hydrocephalus, compression of brain, and reduction of CSF production. Patients are treated by surgically inserting a shunt to deliver excess CSF to the abdominal cavity. The prognosis for cognitive improvement after shunt surgery has been difficult to predict. We therefore investigated various CSF proteins, hoping to find a biomarker predictive of cognitive performance one to two years after shunt surgery. CSF proteins of 34 iNPH and 15 non-iNPH patients were analysed by Western blotting, revealing two glycan isoforms of transferrin (Tf); 'brain-type' Tf with N-acetylglucosaminylated glycans and 'serum-type' Tf with α2, 6-sialylated glycans. Brain-type Tf levels decreased in iNPH but rapidly returned to normal levels within 1-3 months after shunt surgery. This change was positively correlated with recovery from dementia, per Mini-Mental State Examination and Frontal Assessment Battery scores at 11.8 ± 7.7 months post-operation, suggesting that brain-type Tf is a prognostic marker for recovery from dementia after shunt surgery for iNPH. Histochemical staining with anti-Tf antibody and an N-acetylglucosamine-binding lectin suggests that brain-type Tf is secreted from choroid plexus, CSF-producing tissue.

Background: Spontaneous intracranial hypotension (SIH) is caused by cerebrospinal fluid (CSF) leakage. Definitive diagnosis can be difficult by clinical examinations and imaging studies., Methods: SIH was diagnosed with the following criteria: (i) evidence of CSF leakage by cranial magnetic resonance imaging (MRI) findings of intracranial hypotension and/or low CSF opening pressure; (ii) no recent history of dural puncture. We quantified CSF proteins by ELISA or Western blotting., Results: Comparing with non-SIH patients, SIH patients showed significant increase of brain-derived CSF glycoproteins such as lipocalin-type prostaglandin D synthase (L-PGDS), soluble protein fragments generated from amyloid precursor protein (sAPP) and "brain-type" transferrin (Tf). Serum-derived proteins such as albumin, immunoglobulin G, and serum Tf were also increased. A combination of L-PGDS and brain-type Tf differentiated SIH from non-SIH with sensitivity 94.7% and specificity 72.6%., Conclusion: L-PGDS and brain-type Tf can be biomarkers for diagnosing SIH., General Significance: L-PGDS and brain-type Tf biosynthesized in the brain appears to be markers for abnormal metabolism of CSF., (Copyright © 2018. Published by Elsevier B.V.)

While pericytes wrap around microvascular endothelial cells throughout the human body, their highest coverage rate is found in the brain. Brain pericytes actively contribute to various brain functions, including the development and stabilization of the blood-brain barrier (BBB), tissue regeneration, and brain inflammation. Accordingly, detailed characterization of the functional nature of brain pericytes is important for understanding the mechanistic basis of brain physiology and pathophysiology. Herein, we report on the development of a new human brain pericyte cell line, hereafter referred to as the human brain pericyte/conditionally immortalized clone 37 (HBPC/ci37). Developed via the cell conditionally immortalization method, these cells exhibited excellent proliferative ability at 33 °C. However, when cultured at 37 °C, HBPC/ci37 cells showed a differentiated phenotype that was marked by morphological alterations and increases in several pericyte-enriched marker mRNA levels, such as platelet-derived growth factor receptor β. It was also found that HBPC/ci37 cells possessed the facilitative ability of in vitro BBB formation and differentiation into a neuronal lineage. Furthermore, HBPC/ci37 cells exhibited the typical "reactive" features of brain pericytes in response to pro-inflammatory cytokines. To summarize, our results clearly demonstrate that HBPC/ci37 cells possess the ability to perform several key brain pericyte functions while also showing the capacity for extensive and continuous proliferation. Based on these findings, it can be expected that, as a unique human brain pericyte model, HBPC/ci37 cells have the potential to contribute to significant advances in the understanding of human brain pericyte physiology and pathophysiology.

In addition to their well-known role in the female reproductive system, estrogens can act in the brain to regulate a wide range of behaviors and physiological functions in both sexes. Over the past few decades, genetically modified animal models have greatly increased our knowledge about the roles of estrogen receptor (ER) signaling in the brain in behavioral and physiological regulations. However, less attention has been paid to the estrogen-related receptors (ERRs), the members of orphan nuclear receptors whose sequences are homologous to ERs but lack estrogen-binding ability. While endogenous ligands of ERRs remain to be determined, they seemingly share transcriptional targets with ERs and their expression can be directly regulated by ERs through the estrogen-response element embedded within the regulatory region of the genes encoding ERRs. Despite the broad expression of ERRs in the brain, we have just begun to understand the fundamental roles they play at molecular, cellular, and circuit levels. Here, we review recent research advancement in understanding the roles of ERs and ERRs in the brain, with particular emphasis on ERRs, and discuss possible cross-talk between ERs and ERRs in behavioral and physiological regulations., Competing Interests: The authors declare no conflict of interest.

Although carmustine (Gliadel) wafers improve local tumor control and extend the overall survival in patients with malignant glioma, adverse effects have been documented. The authors report the first case of eosinophilic meningitis triggered by the placement of Gliadel wafers. A 61-year-old man with a history of alimentary allergy and glioblastoma in the right frontal lobe underwent resection followed by the implantation of Gliadel wafers. Three weeks later he suffered the sudden onset of headache, vomiting, and progressive consciousness disturbance. Computed tomography revealed enlargement of the ventricular system and subdural space on the side of the tumor. His CSF leukocyte count increased up to 3990 cells/mm 3 ; 95% of the cells were eosinophilic granulocytes (EGs), suggesting eosinophilic meningitis. Laboratory examination showed the patient to have various elevated allergy indicators. The administration of corticosteroids failed to improve his condition. Despite the insertion of a lumbar drain his symptoms failed to improve. He underwent a second surgical intervention to remove the Gliadel wafers. Histologically, EGs had assembled around the wafers. Eosinophilic infiltrate was present in the brain parenchyma around small vessels. After ventriculoperitoneal shunting his course was favorable. A drug lymphocyte stimulation test against the Gliadel wafers failed to demonstrate a positive reaction; polifeprosan, the wafer matrix without 1,3-bis(2-chloroethyl)-1-nitrosourea, yielded a positive reaction. These findings strongly suggest that although extremely rare, polifeprosan (the wafer matrix) can elicit an allergic reaction. When eosinophilic meningitis is suspected after the implantation of Gliadel wafers, their immediate removal should be considered.

Brain magnetic resonance imaging (MRI) of patients with Alzheimer's disease (AD) sometimes reveals multiple cerebral microbleeds (CMBs) and confluent white matter hyperintensities (WMHs) similar to those observed in cerebral amyloid angiopathy-related inflammation (CAA-I). To determine whether there might be common pathophysiological mechanisms underlying the MRI findings of multiple CMBs and confluent WMHs, we investigated the cerebrospinal fluid (CSF) profiles of 38 AD, five amnestic mild cognitive impairment (MCI), and six CAA-I patients. The AD and MCI patients were divided into groups of patients with (n = 10) or without (n = 33) multiple CMBs (n ≥ 2) on T2*-gradient echo sequences of brain MRI. We compared the CSF profiles of AD and MCI patients with or without multiple CMBs, and CAA-I patients. The brain MRIs of the patients with multiple CMBs revealed severe degrees of WMHs compared with the patients without multiple CMBs. The levels of CSF anti-amyloid β autoantibody and interleukin 8, and CSF/serum albumin ratios and immunoglobulin G indexes, were significantly higher in CAA-I patients than the other groups. However, there were no significant differences in the CSF profiles of patients with or without multiple CMBs. Our study provides evidence for different pathophysiological mechanisms underlying these differential MRI findings in AD and CAA-I.

Astrocytes are the most abundant cell types in mammalian brains, within which they participate in various neuronal activities, partly by utilizing the numerous transporters expressed at their plasma membranes. Accordingly, detailed characterization of astrocytic functions, including transporters, are essential for understanding of mechanistic basis of normal brain functions, as well as the pathogenesis and treatment of various brain diseases. As a part of overall efforts to facilitate such studies, this study reports on the establishment of a new human astrocyte cell line, which is hereafter referred to as human astrocyte/conditionally immortalized, clone 35 (HASTR/ci35). This line, which was developed utilizing a cell immortalization method, showed excellent proliferative ability and expressed various astrocyte markers, including glial fibrillary acidic protein. When co-cultured with neuronal cells, HASTR/ci35 cells could facilitate their dendritic network formation. Furthermore, HASTR/ci35 cells not only possessed significant glutamate and adenosine transporter activities but also exhibited organic ion transporter activities. To summarize, HASTR/ci35 cells possess several key astrocytic characteristics, including various transporter functions, while simultaneously showing infinite proliferation and scalability. Based on these findings, HASTR/ci35 cells can be expected to contribute significantly to various human astrocyte study fields. In vitro astrocyte models are valuable experimental tools in various astrocyte studies. Here, we report the establishment of a new human astrocyte cell line, HASTR/ci35, which show various key astrocyte properties, including astrocytic transporter activities, glycogen storage and facilitation of neuronal cell differentiation. Thus, HASTR/ci35 is expected to significantly contribute to advances toward detailed understanding of human astrocyte functions., (© 2015 International Society for Neurochemistry.)

Objective: Estrogens can act in the brain to prevent body weight gain. Tremendous research efforts have been focused on estrogen physiology in the brain in the context of body weight control; estrogen receptors and the related signals have been attractive targets for development of new obesity therapies. The objective is to review recent findings on these aspects., Methods: Recent studies that used conventional and conditional knockout mouse strains to delineate the cellular and molecular mechanisms for the beneficial effects of estrogens on body weight balance are reviewed. Emerging genetic tools that could further benefit the field of estrogen research and a newly developed estrogen-based regimen that produces body weight-lowering benefits also are discussed., Results: The body weight-lowering effects of estrogens are mediated by multiple forms of estrogen receptors in different brain regions through distinct but coordinated mechanisms. Both rapid signals and "classic" nuclear receptor actions of estrogen receptors appear to contribute to estrogenic regulation of body weight., Conclusions: Estrogen receptors and associated signal networks are potential targets for obesity treatment, and further investigations are warranted., (© 2015 The Obesity Society.)

Galectin-3 is a β-galactosidase-binding lectin which is important in cell proliferation and apoptotic regulation. Encephalomyocarditis virus (EMCV), which includes the Enterovirus genus, can cause not only acute myocarditis but also neuronal degeneration of central nervous system in various animals including mice. The pathophysiological role of galectin-3 in central nervous system following acute viral infection is not fully understood. The goal of this study is to determine the localization and time-course of galectin-3 expression after acute viral inoculation with EMCV. Galectin-3 is up-regulated in degenerated lesions of brain area including cerebellum, hippocampus, thalamus and cerebral hemisphere, 96 h after EMCV inoculation. At the same time, Iba-1 positive microglia was morphologically activated within and around the focus of infection. Interestingly, in cerebellum, the microlesions containing a few galectin-3 cells were detected in the immediate-early phase of infection, as early as 48 h after EMCV inoculation. Thus, our results indicate that galectin-3 expression may be a key mediator between viral infection and neuronal degeneration in central nervous system including cerebellum. Furthermore, detection of galectin-3 might be an early diagnostic method for neuronal degeneration after virus infection., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Rationale and Objectives: Many patients with systemic lupus erythematosus (SLE) manifest the recurrence of new brain lesions on follow-up magnetic resonance imaging (MRI) scans. We assessed whether the initial MRI findings help to predict the subsequent development of brain lesions in patients with SLE., Materials and Methods: We enrolled 64 patients with SLE who had undergone initial and follow-up MRI studies. Two radiologists reviewed and categorized the initial MRI findings and divided the patients into those with no lesions on the initial and follow-up MRI scans (group A, n = 18), those with lesions on the initial scans only (group B, n = 32), and those with lesions on the first and new lesions on the follow-up MRI scans (group C, n = 14). We then looked for independent predictors of the subsequent development of brain lesions, such as antiphospholipid syndrome (APS) and findings on the initial MRI studies., Results: The incidence of lacunar and localized cortical infarcts was significantly greater in group C than group B (50% vs. 0%, P < .001 and 50% vs. 9%, P < .05, respectively). Multivariate logistic regression analysis indicated that lacunar or localized cortical infarcts on the initial MRI scans were independent predictors of the subsequent development of brain lesions (odds ratio [OR]: 5.412, 95% confidence interval [CI]: 1.18-24.85, P = .03), whereas the presence of APS was not (OR: 0.621, 95% CI: 0.18-2.19)., Conclusions: The presence of lacunar and/or localized cortical infarcts on initial MRI scans may predict the development of new brain lesions in patients with SLE., (Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: Antiphospholipid syndrome may affect the incidence and pathogenesis of cerebrovascular diseases in patients with systemic lupus erythematosus. We compared the spectrum of MR findings in patients with systemic lupus erythematosus with and without antiphospholipid syndrome., Materials and Methods: We identified 256 patients with systemic lupus erythematosus (45 with, 211 without antiphospholipid syndrome) who underwent MR studies; in 145 (57%), we detected abnormalities. These were categorized as large territorial, lacunar, localized cortical, and borderzone infarctions and as microembolisms, basal ganglia lesions, callosal lesions, hemorrhages, and white matter hyperintensity on T2-weighted and/or FLAIR images, and as stenotic arterial lesions on MR angiograms. Logistic regression analysis was performed to compare the MR findings in patients with systemic lupus erythematosus with and without antiphospholipid syndrome, with patient age and antiphospholipid syndrome as the covariates., Results: Abnormal MR findings were more common in patients with systemic lupus erythematosus with antiphospholipid syndrome (73% versus 53%). Large territorial (P = .01), lacunar (P = .01), localized cortical (P < .01), borderzone infarcts (P < .01), basal ganglia lesions (P = .03), stenotic arterial lesions (P = .04), and the rate of positive findings on MR imaging (P = .01) were significantly associated with antiphospholipid syndrome. Irrespective of age, significantly more patients with antiphospholipid syndrome manifested lacunar infarcts in the deep white matter (P < .01), localized cortical infarcts in the territory of the MCA (P < .01), bilateral borderzone infarcts (P < .01), and anterior basal ganglia lesions (P = .01)., Conclusions: Abnormal MR findings were more common in patients with systemic lupus erythematosus with than in those without antiphospholipid syndrome. Large territorial infarctions, lacunar infarctions in the deep white matter, localized cortical infarctions in the MCA territory, bilateral borderzone infarctions, anterior basal ganglia lesions, and stenotic arterial lesions are common MR findings in patients with systemic lupus erythematosus with antiphospholipid syndrome.

Age-related androgen depletion is known to be a risk factor for various diseases, such as osteoporosis and sarcopenia. Furthermore, recent studies have demonstrated that age-related androgen depletion results in accumulation of β-amyloid protein and thereby acts as a risk factor for the development of Alzheimer's disease. Supplemental androgen therapy has been shown to be efficacious in treating osteoporosis and sarcopenia. In addition, studies in animals have demonstrated that androgens can play a protective role against Alzheimer's disease. However, androgen therapy is not used routinely for these indications, because of side effects. Selective androgen receptor modulators (SARMs) are a new class of compounds. SARMs maintain the beneficial effects of androgens on bone and muscle while reducing unwanted side effects. NEP28 is a new SARM exhibiting high selectivity for androgen receptor. To investigate the pharmacological effects of NEP28, we compared the effects on muscle, prostate, and brain with mice that were androgen depleted by orchidectomy and then treated with either placebo, NEP28, dihydrotestosterone, or methyltestosterone. We demonstrated that NEP28 showed tissue-selective effect equivalent to or higher than existing SARMs. In addition, the administration of NEP28 increased the activity of neprilysin, a known Aβ-degrading enzyme. These results indicate that SARM is efficacious for the treatment of not only osteoporosis and sarcopenia, but also Alzheimer's disease., (© 2013 Published by Elsevier B.V.)

The blood-brain barrier (BBB) is formed by brain microvascular endothelial cells (BMEC) working together with astrocytes and pericytes, in which tight junctions and various transporters strictly regulate the penetration of diverse compounds into the brain. Clarification of the molecular machinery that provides such regulation using in vitro BBB models has provided important insights into the roles of the BBB in central nervous system (CNS) disorders and CNS drug development. In this study, we succeeded in establishing a new cell line, hereinafter referred to as human BMEC/conditionally immortalized, clone β (HBMEC/ciβ), as part of our ongoing efforts to develop an in vitro human BBB model. Our results showed that HBMEC/ciβ proliferated well. Furthermore, we found that HBMEC/ciβ exhibited the barrier property of restricting small molecule intercellular penetration and possessed effective efflux transporter functions, both of which are essential to a functioning BBB. Because higher temperatures are known to terminate immortalization signals, we specifically examined the effects of higher temperatures on the HBMEC/ciβ differentiation status. The results showed that higher temperatures stimulated HBMEC/ciβ differentiation, marked by morphological alteration and increases in several mRNA levels. To summarize, our data indicates that the newly established HBMEC/ciβ offers a promising tool for use in the development of a practical in vitro human BBB model that could make significant contributions toward understanding the molecular biology of CNS disorders, as well as to CNS drug development. It is also believed that the development of a specific culture method for HBMEC/ciβ will add significant value to the HBMEC/ciβ-based BBB model., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Diabetes is characterized by absolute or relative insulin deficiency complicated with microangiopathy, whereas obesity stems from insulin resistance. A psychosomatic approach to obesity and diabetes has been highlighted, including the brain-oriented obesity control system (BOOCS). Impaired deformability of erythrocytes in obese or diabetic patients is closely linked to disturbed microcirculation, and improvement of abnormal erythrocyte rheology is a prerequisite for the prevention and treatment of microangiopathy. Therefore, erythrocyte filterability, whole cell deformability defined as flow rate of erythrocyte suspension relative to that of saline, was assessed by the nickel-mesh-filtration technique. Subjects included healthy controls (group A, n = 14), diabetic, non-obese participants (group B, n = 29), and non-diabetic, obese participants (group C, n = 32) in the 6-month BOOCS program, and most patients in groups B and C (86.9 %) completed this program. Baseline mean erythrocyte filterabilities were 89.4 ± 1.7 % in group A, 82.8 ± 5.2 % in group B, and 84.1 ± 5.6 % in group C, showing significant intergroup differences (p < 0.001). This program significantly improved (p < 0.001) the impaired erythrocyte filterability in groups B (87.9 ± 4.4 %) and C (88.5 ± 3.7 %). Declines in HbA1c (p = 0.387) and body mass index (p = 0.479) were not correlated to this improvement. These findings indicate that the mechanisms of BOOCS-induced improvement of diabetic or obese patients' erythrocyte deformability are multifactorial, and that the BOOCS program for these patients is a holistic, cost-effective, and highly compliant approach possibly ameliorating microcirculation.

The ketogenic diet (KD) is a high-fat, low-protein, low-carbohydrate diet which is effective in the treatment of medically refractory epilepsy. Several theories have been proposed to explain the mechanism underlying the anticonvulsant efficacy of the KD, however, the precise anticonvulsant mechanism of the KD is still unknown. We speculated the mechanism underlying the effect of the KD in patients with intractable epilepsy, based on the results of the [11C] flumazenil (FMZ)-positron emission tomography (PET) study. A patient developed frontal lobe epilepsy at the age of 2 years. At the age of 4 years 11 months, she was admitted to our hospital for the initiation of a KD. At the time of admission, she had several epileptic attacks each day: frequent postural tonic seizures, hypermotor seizures, head nodding, and intermittent loss of consciousness (non-convulsive status epilepticus). MR imaging showed no abnormal signal intensity in the brain. With the KD, the seizure frequency reduced dramatically on the fifth day. Interictal [11C] FMZ-PET was performed before and 2 months after the initiation of the KD. Before the KD, the [11C] FMZ-PET images and [11C] FMZ-PET binding potential (BP) images showed extremely low accumulation of FMZ throughout the cerebral cortex. Two months after the initiation of the KD, significantly increased binding potential of [11C] FMZ was observed, implying the increased binding potential of the benzodiazepine receptors, probably due to the anticonvulsant effect of the KD. These PET findings suggested that KD may control seizures by directly or indirectly increasing the binding potential of the benzodiazepine receptors.

The cellular distribution of SPP1, which we recently identified as a gene with greater expression in the macaque primary motor cortex than in the premotor or prefrontal cortices, was examined in rhesus macaque, common marmoset, and rat brains. In situ hybridization histochemistry revealed that SPP1 mRNA was expressed specifically in pyramidal neurons in layer V of the sensorimotor cortex of the rhesus macaque. These SPP1 mRNA-positive neurons were most abundant in the primary motor area, followed by Brodmann area 5 and the supplementary motor area, in accordance with the distribution of corticospinal neurons. In addition, injection of a retrograde neuroanatomical tracer into the lateral corticospinal tract (CST) of the spinal cord caused labeling of SPP1 positive neurons, indicating the expression of SPP1 in corticospinal neurons. SPP1 was also expressed in the thalamus, brainstem, and spinal ventral horn of the rhesus macaque. Although SPP1 was also detected in the brainstem and spinal cord of the marmoset and the rat, it was not detected in their cerebral cortices. Selective expression in the corticospinal neurons of the sensorimotor cortex of the rhesus macaque suggests that SPP1 plays a critical role in the functional or structural specialization of highly developed corticospinal systems in certain primate species.

To facilitate common marmoset brain research, we produced a DNA microarray with 7557 probe sets derived from the common marmoset brain. Gene expression profiles in the frontal lobe, hippocampus, cerebellum and amygdaloid nucleus were then analyzed and the top 100 probe sets expressed in each structure were compared. The three lists for the frontal lobe, hippocampus and amygdaloid nucleus were very similar but the probe sets for the cerebellum demonstrated specific differences. Some of the genes specifically expressed in cerebellum were analyzed by real-time quantitative PCR to verify the DNA microarray results. Of examined genes, 5 showed extremely strong expression in cerebellum in comparison with the other structures. The results of real-time quantitative PCR were well consistent with the microarray findings, validating our newly developed DNA microarray as a useful tool for brain research with the common marmoset., (Copyright 2009 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.)

Inhibitory neurons play important roles in a number of brain functions. They are composed of GABAergic neurons and glycinergic neurons, and vesicular GABA transporter (VGAT) is specifically expressed in these neurons. Since the inhibitory neurons are scattered around in the CNS, it is difficult to identify these cells in living brain preparations. The glutamate decarboxylase (GAD) 67-GFP knock-in mouse has been widely used for the identification of GABAergic neurons, but their GAD67 expression was decreased compared to the wild-type mice. To overcome such a problem and to highlight the function and morphology of inhibitory neurons, we generated four lines of VGAT-Venus transgenic mice (lines #04, #29, #39 and #49) expressing Venus fluorescent protein under the control of mouse VGAT promoter. We found higher expression level of Venus transcripts and proteins as well as brighter fluorescent signal in line #39 mouse brains, compared to brains of other lines examined. By Western blots and spectrofluorometric measurements of forebrain, the line #39 mouse showed stronger GFP immunoreactivity and brighter fluorescent intensity than the GAD67-GFP knock-in mouse. In addition, Venus was present not only in somata, but also in neurites in the line #39 mouse by histological studies. In situ hybridization analysis showed that the expression pattern of Venus in the line #39 mouse was similar to that of endogenous VGAT. Double immunostaining analysis in line #39 mouse showed that Venus-expressing cells are primarily immunoreactive for GABA in cerebral cortex, hippocampus and cerebellar cortex and for GABA or glycine in dorsal cochlear nucleus. These results demonstrate that the VGAT-Venus line #39 mouse should be useful for studies on function and morphology of inhibitory neurons in the CNS.

NXF, a brain-specific bHLH-PAS transcription factor, can regulate the transcription of target genes forming heterodimer complexes, along with several other bHLH-PAS family members (Arnt1, Arnt2, BMAL1) in vitro. To characterize its dimerization partner protein(s) in vivo, we performed a co-immunoprecipitation analysis of whole brain extracts using anti-NXF IgG. In the protein fraction co-precipitating with the NXF protein, in addition to the major precipitate of Arnt2 protein, a faint protein band of Arnt1 protein was consistently observed. The following in vitro co-precipitation analysis with recombinant proteins and yeast-two-hybrid analysis confirmed the specific physical associations. Reporter gene analyses further revealed comparable levels of transcriptional activity with Arnt1:NXF and Arnt2:NXF combinations. mRNA expression for Arnt1 was found in several NXF-containing regions in brain, even an example with no Arnt2 expression. The data thus suggest that Arnt1, as well as Arnt2, could have the separate significance for NXF signaling, with Arnt1: NXF heterodimer complexes in vivo.

We report an autopsy case of a 67-year-old man clinicogenetically diagnosed as having spinal muscular atrophy (SMA) type III (Kugelberg-Welander disease), showing slowly progressive muscle wasting and weakness of the extremities. His brother showed similar manifestations. Autopsy revealed neuronal loss and severe gliosis in the anterior horns of the spinal cord, a marked neurogenic change of skeletal muscles and mild degeneration of cardiomyocytes. Chromatolytic change was seen in the anterior horn, but not in the Clarke's and thalamic nuclei. The anterior spinal roots were atrophic, and there was loss of myelinated fibers with abundant glial bundles. In addition, degeneration was also observed in the posterior column and dentate nucleus. The pathological features were essentially similar to those of SMA I. Chronic change was prominent while acute change was mild in degree, corresponding to a very long clinical course.

While neurotrophin is known to be involved in a variety of neuronal functions inducing several immediate early genes and activating several signaling molecules, the correspondence with downstream cascades remains to be defined in detail. Here we show that a bHLH-PAS transcription factor, NXF, is a new member genes under the control of neurotrophin. The PI3K-Akt system, an important cell-protection-signaling cascade under the control of the neurotrophin receptor, was also revealed to contribute to the mechanism of NXF mRNA induction. Activation of MAPK under the control of the neurotrophin receptor resulted in NXF protein phosphorylation as well as enhancement of NXF transcriptional activity. This newly identified NXF gene system may provide a new insight into neurotrophin biology, which reflects the target gene functions.

The pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) may be related to autoantibody-mediated neural dysfunction, vasculopathy and coagulopathy. We encountered an NPSLE patient whose brain showed characteristic diffuse symmetrical hyperintensity lesions in the cerebral white matter, cerebellum and middle cerebellar peduncles on T2-weighted magnetic resonance (MR) images. In this study, we investigated all the antigens that reacted strongly with autoantibodies in this patient's serum by two-dimensional electrophoresis (2DE), followed by western blotting (WB) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) using rat brain proteins as the antigen source. As a result, we identified four antigens as beta-actin, alpha-internexin, 60 kDa heat-shock protein (Hsp60) and glial fibrillary acidic protein (GFAP). There are several reports on the detection of anti-endothelial cell antibodies (AECAs) in an SLE patients. Recently, one of the antigens reacting with AECAs in SLE patient's sera has been identified as human Hsp60. We speculated that the abnormal findings on brain MR images of our patient may be due to impairment of microcirculation associated with vascular endothelial cell injury mediated by the antibody against Hsp60. This proteomic analysis is a useful tool for identifying autoantigens in autoimmune diseases involving autoantibodies.

Murine acquired immunodeficiency syndrome (MAIDS) induced by LP-BM5 murine leukemia virus is used as a model of human immunodeficiency virus (HIV)-related neurologic dysfunction. Mice infected with LP-BM5 have mnemonic abnormalities (i.e., spontaneous alternation behavior in the Y-maze and performance in the Morris water maze) and biochemical alternations (i.e., cytokines, platelet-activating factor, quinolinate, glutamate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor) that produce neurologic symptoms similar to those observed in HIV-related neurologic dysfunction. To identify proteins associated with dysmnesia in the MAIDS model, we examined the expression of neuronal proteins in LP-BM5-infected mice using two-dimensional polyacrylamide gel electrophoresis (2-DE). Neuronal protein expression in LP-BM5-infected mice was compared with that in non-infected mice using the Image Master 2D. We detected approximately 800 protein spots, of which 35 were distinguishable between non-infected and LP-BM5-infected mice. Most of these spots were downregulated in LP-BM5-infected mice. Three of the spots were identified as 14-3-3 protein zeta/delta, synapsin 2 and protein disulfide isomerase using a capillary nanoliquid chromatography tandem mass spectrometric system. We verified the expression levels of these proteins by Western blot. Analysis of these 35 spots could provide insight into mechanisms of dysmnesia in the MAIDS model of HIV-related neuronal dysfunction.

Objective: Focused, highly targeted radiosurgery and fractionated radiotherapy using the Cyberknife are useful treatments for multiple or large metastases. Here we present our results of Cyberknife radiosurgery for 71 patients with 148 metastatic brain lesions., Methods: There were 32 women and 39 men with a median age of 63 (range: 30-88) years. Radiographic follow-up was available for 60 patients with 104 lesions. The mean and median initial volumes of the tumor per lesion were 6.6 and 2.9 cm(3) (range: 0.1-53.2 cm(3)), respectively, at the time of the initial Cyberknife treatment. Forty patients (56%) had a single lesion, and 31 (44%) had multiple lesions (range: 2-7) at initial treatment. The number of fractions ranged from 1 to 3, and forty (27%) of 148 lesions were treated by a fractionated course of Cyberknife therapy. The mean marginal dose was 20.2 Gy (range 7.8-30.1 Gy, median: 20.7 Gy)., Results: At 44 weeks of median follow-up, there were no permanent symptoms resulting from radiation necrosis. Overall 6-month and 1-year survival rates were 74% and 47%, respectively, and the median survival time was 56 weeks. The Karnofsky performance score and extracranial metastasis were significant prognostic factors at 6 months and 1 year, respectively, in both univariate and multivariate analyses. Age or multiple metastases did not influence prognosis at 6 months and 1 year. Local control was achieved in 83% (86 lesions). After additional radiosurgical or surgical salvage, no patient died as a result of intracranial disease. Twenty-five patients developed 92 new metastases (range 1-13) outside of the treated lesions with 22.4 weeks of median follow-up. Among them, 21 patients (84 lesions) were treated by salvage Cyberknife., Conclusion: Despite the inclusion of an unfavorable group of patients with large tumors, our results for survival and tumor control rates are comparable to those of published series. The Cyberknife provides the advantage of allowing for fractionated treatment to multiple or large-size tumors.

For the understanding of histogenetic events in the three-dimensional brain primordia, direct observation of progenitor cells and young neurons is required. Although slice culture, which is one of the tissue or organ culture methods, effectively preserves the in vivo microenvironment where normal developmental processes occur, conventional phase-contrast microscopic observation of brain slices fails to provide good visibility of single cells. However, a combination of slice culture with the use of fluorescent dyes and/or the introduction of fluorescent protein genes provides live, three-dimensional information on cytogenetic and histogenetic events at the individual cell level. Dynamic cellular behaviors can then be vividly captured without destroying tissue structures.

Mature neocortical layers all derive from the cortical plate (CP), a transient zone in the dorsal telencephalon into which young neurons are continuously delivered. To understand cytogenetic and histogenetic events that trigger the emergence of the CP, we have used a slice culture technique. Most divisions at the ventricular surface generated paired cycling daughters (P/P divisions) and the majority of the P/P divisions were asymmetric in daughter cell behavior; they frequently sent one daughter cell to a non-surface (NS) position, the subventricular zone (SVZ), within a single cell-cycle length while keeping the other mitotic daughter for division at the surface. The NS-dividing cells were mostly Hu+ and their daughters were also Hu+, suggesting their commitment to the neuronal lineage and supply of early neurons at a position much closer to their destiny than from the ventricular surface. The release of a cycling daughter cell to SVZ was achieved by collapse of the ventricular process of the cell, followed by its NS division. Neurogenin2 (Ngn2) was immunohistochemically detected in a certain cycling population during G1 phase and was further restricted during G2-M phases to the SVZ-directed population. Its retroviral introduction converted surface divisions to NS divisions. The asymmetric P/P division may therefore contribute to efficient neuron/progenitor segregation required for CP initiation through cell cycle-dependent and lineage-restricted expression of Ngn2.

Blood-brain-barrier (BBB)-permeable, 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy (MC-PROXYL) and BBB-impermeable carbamoyl-PROXYL were used to assess the ESR imaging technique by comparing with autoradiography. For this purpose, spin probes, 14C-labeled at their five-membered ring, [14C]MC-PROXYL and [14C]carbamoyl-PROXYL, were newly synthesized. These probes were i.p. or i.v. injected into rats and autoradiograms were recorded. The autoradiograms of rat head showed that [14C]MC-PROXYL distributed well in the brain compared to [14C]carbamoyl-PROXYL. In vivo ESR spectra and two-dimensional ESR images of isolated rat brain treated with MC- or carbamoyl-PROXYL also indicated the extensive distribution of MC-PROXYL but not carbamoyl-PROXYL in the rat brain. The three-dimensional ESR images of the head of rats and mice were consistent with the fact that MC-PROXYL but not carbamoyl-PROXYL is incorporated into the brain. The ESR-CT images were better for mice than rats. However, the quality of the ESR-CT images was still not satisfactory. Although the resolution and sensitivity of the ESR-CT images were worse than those of the autoradiographic images, the former technique has unique features and advantages; e.g., functional, noninvasive and three-dimensional detection.

Muscle-eye-brain disease (MEB), an autosomal recessive disorder prevalent in Finland, is characterized by congenital muscular dystrophy, brain malformation and ocular abnormalities. Since the MEB phenotype overlaps substantially with those of Fukuyama-type congenital muscular dystrophy (FCMD) and Walker-Warburg syndrome (WWS), these three diseases are thought to result from a similar pathomechanism. Recently, we showed that MEB is caused by mutations in the protein O-linked mannose beta1,2-N-acetylglucosaminyltransferase 1 (POMGnT1) gene. We describe here the identification of seven novel disease-causing mutations in six of not only non-Finnish Caucasian but also Japanese and Korean patients with suspected MEB, severe FCMD or WWS. Including six previously reported mutations, the 13 disease-causing mutations we have found thus far are dispersed throughout the entire POMGnT1 gene. We also observed a slight correlation between the location of the mutation and clinical severity in the brain: patients with mutations near the 5' terminus of the POMGnT1 coding region show relatively severe brain symptoms such as hydrocephalus, while patients with mutations near the 3' terminus have milder phenotypes. Our results indicate that MEB may exist in population groups outside of Finland, with a worldwide distribution beyond our expectations, and that the clinical spectrum of MEB is broader than recognized previously. These findings emphasize the importance of considering MEB and searching for POMGnT1 mutations in WWS or other congenital muscular dystrophy patients worldwide.

Subacute sclerosing panencephalitis is an encephalopathy caused by a persistent measles virus infection. We examined a 13-year-old girl with subacute sclerosing panencephalitis and performed a magnetic resonance spectroscopic study to evaluate the in vivo pathophysiologic abnormality. The results suggested the occurrence of inflammatory processes and glial proliferation prior to neuronal loss even in magnetic resonance imaging (MRI)-negative regions as well as in MRI-positive regions. The additional resonance peaks were also detected, but further studies should be performed to determine the precise pathophysiologic mechanisms. Novel in vivo modalities such as spectroscopy would be useful as a tool to measure responses to therapy.

We investigated the differential distribution of basement membrane type IV collagen a chains in the mouse brain by immunohistochemistry using a chain-specific monoclonal antibodies. Subendothelial basement membranes were found to contain alpha1 and alpha2 chains. Basement membranes surrounding smooth muscle cells on blood vascular walls were immunoreactive for alpha1 and alpha2 chains but not for alpha5 and alpha6 chains. Interestingly, the pia mater contained a thin basement membrane which was positive for alpha1, alpha2, alpha5, and alpha6 chains, suggesting that glia limitans superficialis coheres basement membranes containing [alpha1(IV)]2alpha2(IV) and [alpha5(IV)]2alpha6(IV) molecules. In contrast, capillaries always possessed thin basement membranes of [alpha1(IV)]2alpha2(IV) molecules. Cerebrospinal fluid is produced through filtration of blood at the choroid plexus, where two distinct basement membranes were detected by anti-al and anti-alpha2 antibodies. The subendothelial basement membrane appeared to consist of [alpha1(IV)]2alpha2(IV) molecules, whereas the subependymal basement membrane in the choroid plexus was strongly positive for alpha3, alpha4, and alpha5 chains, indicating that the filtering unit was composed of alpha3(IV)alpha4(IV)alpha5(IV) molecules. That the specific localizations of these molecules are shared by renal glomeruli and the choroid plexus leads us to hypothesize that the supramolecular network containing alpha3(IV) alpha4(IV)alpha5(IV) molecules may function as a permeability selective barrier.

The first reported female patient with the Fukuyama type of congenital muscular dystrophy associated with a lack of C-terminal domain of dystrophin is presented. Clinically, the patient had characteristic features and magnetic resonance imaging findings of Fukuyama muscular dystrophy. Dystrophin analysis revealed a lack of the C-terminal domain but preserved N-terminal and rod domains of dystrophin in biopsied muscle. Moreover, she had reduced expression of merosin, syntrophin, and beta-dystroglycan in the skeletal muscle. Reverse transcriptase-polymerase chain reaction analysis of mRNA in the patient's muscle illustrated a complete lack of exons 71-74 of the dystrophin gene. These deletions, which remove the beta-dystroglycan and syntrophin binding site, may cause changes in the function of both beta-dystroglycan and syntrophin in human muscle.

Fukuyama type congenital muscular dystrophy (FCMD) is an autosomal recessive disorder characterized by progressive muscular dystrophy and dysgenesis of the central nervous system and eyes. To clarify the pathomechanism of the ocular involvement in FCMD, we performed postmortem pathological analyses of eyes from three postnatal FCMD cases, two fetal FCMD cases, and three control cases by macroscopic, histopathological, immunohistochemical and in situ hybridization approaches. The macroscopic and histopathological examinations revealed a variety of ocular abnormalities such as folding, fusion or dysplasia of the retinas in the FCMD cases both with and without ophthalmological alterations. Immunoreactivities for collagen IV and laminin, produced by Müller cells, as the basement membrane components, were less intense in the inner limiting membrane of the FCMD retinas than in that of the control retinas. A number of the perivascular glial cells containing S-100 protein and glial fibrillary acidic protein were increased in the postnatal FCMD cases. Immunoreactivities for vimentin, glutamate transporter-1, glutamine synthase and ornithine aminotransferase, expressed in the Müller cells, were undetectable in the fetal FCMD retinas, and reduced in the postnatal FCMD retinas compared with the control retinas. Fukutin mRNA signals were distributed diffusely in the retinoblast layer of the control retinas, focally in the retinoblast layer of the fetal FCMD retinas, and only in the dysplastic areas with rosette formation of the postnatal FCMD retinas, composed of retinoblasts and other retinal cells including the Müller cells. The present findings suggest that the Müller cells are implicated in the retinal pathology of FCMD.

It is well known that prophylactic cranial irradiation is highly effective in preventing central nervous system (CNS) relapse of acute lymphoblastic leukemia (ALL). Nevertheless, there have been very few reports on the late effects, especially pituitary function and growth, in long-term survivors who were treated with 18 Gy cranial irradiation in childhood. The subjects consisted of 35 children with ALL who were treated with prophylactic 18 Gy cranial irradiation at Kanagawa Children's Medical Center between October 1981 and February 1995. All patients received cranial irradiation after first attaining complete remission with induction chemotherapy, according to the treatment protocols prescribed by the Tokyo Children's Leukemia Study Group (TCLSG) and Tokyo Children's Cancer Study Group (TCCSG). Their ages at the time of cranial irradiation ranged from 2.2-15.0 years (mean 6.8). We evaluated their pituitary functions by measuring their pituitary hormone values 0.7-11.3 years (mean 6.0) after cranial irradiation and their growth by analyzing their height standard deviation score (SDS) at diagnosis of ALL and their final height SDS at the mean follow-up period of 8.2 years after cranial irradiation. Height SDS is defined as the difference between the patient's height and the mean height of their age and sex, divided by the standard deviation of their age and sex. Eight of 35 patients had ALL relapse, involving the bone marrow in seven patients and the CNS in only one. Six of the eight patients with relapse died 1.5-6.6 years after cranial irradiation and the other two patients were salvaged by further intensive therapies. The remaining 27 relapse-free patients have survived for 1.4-15.8 years (mean 10.1) after cranial irradiation. Twenty-six of the 29 survivors are long-term survivors of more than 5 years. Although there was one patient with an abnormal result in each value of growth hormone (GH), adrenocorticotropic hormone (ACTH), and prolactin (PRL), and two patients with abnormal results in thyroid-stimulating hormone (TSH) values, none of the patients had clinical symptoms of pituitary hormone abnormality and none required hormone supplements. The final height SDS decreased significantly compared with the height SDS at diagnosis of ALL in the long-term survivors (P = 0.001) and the height SDS of the patients who had received cranial irradiation at a young age tended to decrease gradually (P = 0.019). However, no patient showed severe growth failure. It is considered that prophylactic 18 Gy cranial irradiation plus chemotherapy for ALL in childhood can effectively prevent CNS relapse and is unlikely to produce clinically significant late effects, although it may cause slight pituitary hormone abnormality., (Copyright 2002 Wiley-Liss, Inc.)

Blooms of Pfiesteria piscicida, a dinoflagellate in eastern U.S. coastal rivers, are believed to secrete toxins that kill fish and produce short-term memory loss in humans. Only one or two of Pfiesteria's multiple stages secrete the toxin, and only under certain environmental conditions. Thus, neither the presence of Pfiesteria nor fish kill alone can be indicative of toxin presence. The objective of this study was to identify the mammalian molecular brain target for the toxin that is associated with decrements in memory. Seven rat brain neurotransmitter receptors were selected to study because of their reported roles in cognitive function: receptors for nicotine, muscarine, AMPA/kainate, N-methyl-D-aspartate (NMDA), gamma-aminobutyric acid, and dopamine 1 and 2. The effects of 17 environmental and laboratory samples on radioactive ligand binding to these receptors were studied. Of the seven receptors, binding only to the NMDA receptor was inhibited by only the two Pfiesteria-containing waters (identified by PCR) that also killed fish, and not by any of the other 15 samples tested. It is suggested that inhibition of NMDA-receptor binding is the cause of memory loss in exposed humans. Thus, it could be a useful biomarker for the toxin's presence in rivers for decisions on closures and for identification of the fractions containing the toxin during its purification. Knowledge of the toxin's molecular target, and how it affects its function, also leads to suggestions for therapeutics to use in animal models., (Copyright 2000 Academic Press.)

A 74-year-old man developed abnormal forgetfulness, soon followed by unstable speech content and marked disorientation. At 77 years of age, the patient started to occasionally fall, an aspect of progressive supranuclear palsy. He then became bedridden. The patient eventually died of pneumonia at 79 years of age. Neuropathological examination revealed profiles of both progressive supranuclear palsy and Alzheimer's disease. Although the two conditions both belong to tauopathy, their pathologically proven combination was rare. Furthermore, the case had the possibility of being a subgroup of tauopathy.

The influence of oxidative stress in rat brain and liver on intrauterine growth retardation (IUGR) in rat fetuses was examined. Twenty pregnant Wistar rats were used. On the 15th day of pregnancy, uterine artery and vein were ligated bilaterally using a modified Wigglesworth method. On the 21st day of pregnancy, the fetuses were delivered by hysterotomy. Fetal blood was collected by cardiac puncture. Fetal brain and liver were removed for the analysis of lipid peroxide. Sham surgical operations were performed in the control rats. Within the ligated group, a superoxide dismutase mimicking substance, Fe-chlorine e6-Na (FeCNa), was injected intraperitoneally once a day from day 15 of gestation to day 20. Fetal blood, brain, and liver were stored at -70 degrees C until analysis. Control rats received an equivalent volume of saline. In growth-retarded fetuses, both superoxide released from erythrocytes and brain lipid peroxide showed significantly higher levels, but not superoxide dismutase in erythrocytes and liver lipid peroxide. These changes were alleviated by injection of superoxide dismutase-mimicking substance, FeCNa. Rat fetuses with intrauterine growth retardation suffered from a significant oxidative stress in utero. The increase in reactive oxygen species was alleviated by an injection of FeCNa., (Copyright 2000 S. Karger AG, Basel)

Immunohistochemical localization of Copper-transporting P-type ATPase (ATP7B), a gene product responsible for Wilson disease, was visualized in the brain tissues of the Long-Evans agouti rat in detail using tissue-blotting technique and confocal laser microscopy. The ATP7B was intensely detected in neuronal cells of the hippocampal formation, olfactory bulbs, cerebellum, cerebral cortex and nuclei in the brainstem in which high amounts of copper and cuproenzymes, dopamine beta hydroxylase and Cu,Zn-superoxide dismutase (Cu,Zn-SOD) were detected. The present results suggest that ATP7B plays key roles in neurotransmissions of catecholamine pathway and preventing brain tissues from injury by superoxide radicals to regulate the cellular Cu concentration and/or activities of cuproenzymes related to neurotransmissions and a free radical metabolism. Furthermore, it is reasonable to assume that neurotoxicity due to abnormal copper accumulation or irregular regulation of cuproenzymes in the critical brain regions by mutation of the ATP7B gene leads to neurological failures of Wilson disease.

Anthranilic acid (AA) has attracted considerable attention as one of the L-tryptophan-kynurenine pathway metabolites in the central nervous system. In this study, a highly sensitive and accurate method for the quantification of AA has been developed using reversed-phase high-performance liquid chromatography with electrochemical detection. Serum and cerebrospinal fluid (CSF) AA concentrations in different animal species were measured. CSF AA concentrations in rabbits were 1.1 +/- 0.1 nmol/liter, which were 5. 7-33.0 times lower than those in other species studied. Serum AA concentrations, however, were slightly higher in rabbits than in other species. In contrast, the concentrations of L-kynurenine (L-KYN) in both serum and CSF were substantially higher in rabbits than in other species. Tissue kynurenine pathway enzymes, indoleamine 2,3-dioxygenase (IDO), tryptophan 2,3-dioxygenase, kynurenine 3-hydroxylase, and kynureninase were determined in rabbits, rats, gerbils, and mice. These enzymes varied among species, especially lung IDO activities in rabbits were 146-516 times higher than those found in other species, but rabbit liver kynurenine 3-hydroxylase activities were lower by one order of magnitude than those of the other species tested. Furthermore, brain kynurenine 3-hydroxylasae activities were 12.3-23.2 times higher in gerbils than those in the other species tested. In addition, AA concentrations in serum following intravenous administration of L-KYN (5 mg/kg) were also measured in rabbits. AA levels peaked sharply within 5 min after administration and decreased in a time-dependent manner. At 5 min after administration, CSF L-KYN and AA concentrations were also increased by 1.76- and 2.56-fold, respectively, compared with basal levels. Increased AA concentrations in CSF following L-KYN administration may reflect the entry of AA into the CSF after conversion to AA in systemic tissue and/or the local synthesis of AA from L-KYN in the CNS., (Copyright 1998 Academic Press.)

This study investigated the sources of quinolinic acid, a neurotoxic tryptophan-kynurenine pathway metabolite, in the brain and blood of HIV-infected patients and retrovirus-infected macaques. In brain, quinolinic acid concentrations in HIV-infected patients were elevated by > 300-fold to concentrations that exceeded cerebrospinal fluid (CSF) by 8.9-fold. There were no significant correlations between elevated serum quinolinic acid levels with those in CSF and brain parenchyma. Because nonretrovirus-induced encephalitis confounds the interpretation of human postmortem data, rhesus macaques infected with retrovirus were used to examine the mechanisms of increased quinolinic acid accumulations and determine the relationships of quinolinic acid to encephalitits and systemic responses. The largest kynurenine pathway responses in brain were associated with encephalitis and were independent of systemic responses. CSF quinolinic acid levels were also elevated in all infected macaques, but particularly those with retrovirus-induced encephalitis. In contrast to the brain changes, there was no difference in any systemic measure between macaques with encephalitis vs. those without. Direct measures of the amount of quinolinic acid in brain derived from blood in a macaque with encephalitis showed that almost all quinolinic acid (>98%) was synthesized locally within the brain. These results demonstrate a role for induction of indoleamine-2,3dioxygenase in accelerating the local formation of quinolinic acid within the brain tissue, particularly in areas of encephalitis, rather than entry of quinolinic acid into the brain from the meninges or blood. Strategies to reduce QUIN production, targeted at intracerebral sites, are potential approaches to therapy.

In vivo microdialysis was used to investigate nicotinic receptor-mediated acetylcholine release in the hippocampus, frontal cortex, and striatum of freely moving rats. Intraperitoneal administration of (-)-nicotine increased the release of acetylcholine in the hippocampus and frontal cortex but not in the striatum. (-)-Nicotine exhibited a bell-shaped dose-response relationship, and showed attenuation of response at the highest dose (5.0 mg/kg i.p.) in both the hippocampus and frontal cortex. In the hippocampus, (-)-nicotine (1.0 mg/kg i.p.)-induced increase of acetylcholine release was blocked by pretreatment with the centrally acting nicotinic receptor channel blocker, mecamylamine (1.0 mg/kg i.p.), but not by hexamethonium (5.0 mg/kg i.p.), suggesting that the effects of (-)-nicotine were mediated by the central nicotinic receptor. (S)-3-methyl-5-(1-methyl-2-pyrrolidinyl)isoxazole (ABT-418, 1.0 and 5.0 mg/kg i.p.), reported to be a selective agonist for alpha4beta2 nicotinic receptor subunits, also enhanced the release of acetylcholine in the hippocampus, while 3-(2,4-dimethoxybenzlidene)-anabaseine (GTS-21, 1.0 and 5.0 mg/kg i.p.), which has high affinity for the alpha7 nicotinic receptor subunit, was without effect. The natural alkaloids isolated from plants, (-)-cytisine and (-)-lobeline, had little effect on acetylcholine release from the hippocampus. A competitive antagonist for alpha4beta2 subunits of the nicotinic receptor, dihydro-beta-erythroidine, and a partial agonist for the beta2 subunit-containing nicotinic receptor, (-)-cytisine, inhibited (-)-nicotine-induced increase of acetylcholine release from the hippocampus, whereas a selective antagonist for the alpha7 subunit, methyllycaconitine, and a partial agonist for the alpha3 subunit-containing nicotinic receptor, (-)-lobeline, did not. These results indicate that there are certain differences among brain regions in the response of nicotinic receptor-mediated acetylcholine release and that (-)-nicotine-induced acetylcholine release in the rat hippocampus may be attributed to activation of the alpha4beta2 nicotinic receptor subunits.