bluuebunny/crossref_metadata_2025 huggingface dataset:
Hirano bodies and chronic alcoholism
Authors: Laas R. , Hagel C.
Published: May 2008

Experiments on rodents have shown convincingly that chronic ethanol ingestion may damage the hippocampal formation. Nevertheless this region has, hitherto, not been considered as a target for alcoholism–induced brain lesions in man. Guided by the observation of increased numbers of Hirano bodies (HB) in the hippocampus of chronic alcoholics, this study determines the maximum number of HB per high power field (HPF: 0.19 mm2) in the stratum pyramidale (HBpyr) and in the stratum lacunosum (HBlac) of Ammon's horn in 123 chronic alcoholics and in 197 controls. The average count of HBlac found in alcoholics was 14.4 (SD = 17.7) compared with 4.2 (SD=7.4) in non–alcoholics (P < 0.001). Counts of more than 19 HBlac per HPF were revealed as highly indicative of chronic alcoholism being observed in 33 (27%) alcoholics and in six (3%) non–alcoholics (P < 0.001). An increased number of HBlac was the most frequent of the neuropathological findings in the alcoholics. Affirming observations of others, the count of HBlac peaked during middle age and declined thereafter. The maximum count of HBpyr, in contrast, increased with age and was independent of alcoholism. It is proposed that increased numbers of HBlac indicate alterations of the apical dendrites of the pyramidal neurons of the CA1 field of Ammon's horn which probably are due to direct neurotoxic effects of ethanol and which may be reversible in nature.
Ubiquitin and neurofilament expression in anterior horn cells in amyotrophic lateral sclerosis: possible clues to the pathogenesis
Authors: Migheli A. , Attanasio A. , Schiffer D.
Published: May 2008

Cytoskeletal abnormalities are a prominent pathological feature of anterior horn cells in amyotrophic lateral sclerosis (ALS), and are thought to be involved in the process of motor neuron death. Skein–like filamentous inclusions have been detected by immunocytochemical staining for ubiquitin, a stress protein involved in targeting abnormal proteins for proteolysis. So far, identification of the target protein has been elusive. We have studied the ultrastructural localization of ubiquitin and neurofilaments by post–embedding immunogold staining. In skein–like arrays, strong ubiquitin labelling was concentrated on abnormally formed 15–20 nm filaments; neurofilament labelling was localized on 10 nm filaments adjacent or in continuity with the abnormal filaments. In addition, Bunina bodies were a major site of ubiquitin accumulation. Our results suggest that ubiquitinated filaments in skein–like inclusions might originate from abnormally aggregated neurofilament proteins, which are no longer recognized by antibodies to neurofilament epitopes. Furthermore, the presence of ubiquitin in Bunina bodies suggests that, in addition to its protective role, ubiquitin might be directly implicated in the mechanism of programmed neuronal death in ALS.
Magnetic resonance imaging evaluation of the effects of ageing on grey–white ratio in the human brain
Authors: Harris G. J. , Schlaepfer T. E. , Peng L W. , Lee S. , Federman E. B. , Pearlson G. D.
Published: May 2008

A previous neuropathological report noted a non–linear pattern of change in cerebral grey–white matter ratio during ageing. In that report, grey–white ratio decreased from age 20 to age 50, then increased in elderly subjects. The objective of the current study was to attempt to replicate this pattern of age–related change in the grey–white ratio in living human subjects using quantitative magnetic resonance imaging segmentation analysis. We measured the grey–white ratio in 78 subjects between the ages of 19 and 77 years, using a computer segmentation algorithm with magnetic resonance images. In agreement with the previous neuropathological report. the current in vivo magnetic resonance study found that the grey–white ratio declined from age 20 to age 50, then increased in elderly subjects.
Dorothy Russell Memorial Lecture The molecular pathology of Alzheimer's disease: are we any closer to understanding the neurodegenerative process?
Authors: Smith C. , Anderton B. H.
Published: May 2008

Alzheimer's disease, the most common cause of dementia in the elderly, is rapidly becoming epidemic in the western world, with major social and economic ramifications. Thus enormous international scientific efforts are being made to increase our understanding of the pathogenesis of this disease, with the eventual goal of developing beneficial therapy. The two major neuro–pathohgical hallmarks of Alzheimer's disease (AD) are extracellular senile plaques, the principal component of which is the Aβ amyloid peptide, and intraneuronal neurofibrillary tangles, which are composed of aggregated tau protein in the form of paired helical filaments (PHF). In the past decade, since the major proteinaceous components of these pathological markers have been identified, great strides have been made in elucidating the biochemical processes which may underlie their abnormal deposition and aggregation in Alzheimer's disease. Simultaneously, extensive population genetic analyses have identified mutations in the Aβ amyloid precursor protein (APP) in a small number of pedigrees with familial Alzheimer's disease (FAD) whilst other FAD cases have been linked to an, as yet, unidentified marker on chromosome 14. Most recently, inheritance of the type 4 allele of apolipoprotein E has also been identified as a risk factor in sporadic AD. The challenge facing scientists now is to incorporate this wealth of exciting new biochemical and genetic data into a coherent model which can explain the long established neurochemical and histopathological lesions characteristic of AD.
Analysing brain function and dysfunction in transgenic animals
Authors: Lathe R. , Morris R. G. M.
Published: May 2008

Many neuropsychiatric disorders have a genetic aetiology. In vivo gene modification offers a route to simulating such disorders in transgenic animals, allowing a systematic study of the underlying pathophysiology. However, attempts to mimic diseases such as Alzheimer's disease in transgenic animals have not yet been successful. This principally reflects our lack of knowledge concerning normal brain function, and an understanding of the biochemical mechanisms underlying cognitive processes is a primary objective. We and others have therefore focused on the hippocampus, a brain region involved in learning and memory and an early target for degeneration in Alzheimer's disease. Genetic intervention to date has yielded transgenic animals with apparent functional deficits in the hippocampus, leading the way to a greater understanding of brain function.
Prion protein immunocytochemistry: reliable protocols for the investigation of Creutzfeldt–Jakob disease
Authors: Hayward P. A. R. , Bell J. E. , Ironside J. W.
Published: May 2008

Current criteria for the histological diagnosis of Creutzfeldt–Jakob disease (CJD) include features such as spongiform change, neuronal loss and reactive gliosis which are shared to a varying extent with other neurodegenerative disorders. Reliable visualization of prion protein (PrP) has substantial potential value in diagnostic practice and as a research tool, since accumulation of the disease–associated isoform of this protein is apparently specific for spongiform encephalopathies. A number of antisera against PrP have previously been employed in conjunction with a range of pre–treatments designed to optimize the specificity of immunostaining; such varied usage makes the comparison and interpretation of results difficult. This study was undertaken to identify optimal combinations of each of three PrP antisera and five pre–treatments designed to specifically demonstrate disease–specific PrP in a series of seven CJD cases, six cases of Alzheimer–type dementia and six non–demented control cases. Specific staining of amyloid plaques, spongiform neuropil, neurons and, occasionally, astrocytes was achieved in CJD cases. Alzheimer and control cases were unstained. Use of formic acid with guanidine thiocyanate, and hydrolytic autoclaving with IB 3 and SP30 antisera proved most effective and can be recommended for future immunocytochemical studies. PrP immunocytochemistry revealed a greater extent of subcortical neural involvement than routine histological techniques in CJD; the relationship between classical neuropathology in CJD and PrP accumulation as revealed by immunocytochemistry is not clear cut and requires further investigation. These findings may help to broaden our understanding of human spongiform encephalopathies, and have implications for diagnostic practices in neuropathology.
MHC Class II expression by microglia in tetanus toxin–induced experimental epilepsy in the rat
Authors: Shaw J. A. G. , Perry V. H. , Mellanby J.
Published: May 2008

Minute amounts of tetanus toxin injected into the hippocampus of rats results in an epileptiform syndrome. When the toxin injection is made unilaterally or bilaterally into the ventral hippocampus, about one–third of animals with seizures show bilateral neuronal loss in dorsal CA1 of the hippocampus after 1 week. In animals with seizures, microglia in hippocampus are found to be activated. The present work shows that during the acute phase, microglia in the substantia nigra become activated and express MHC class II antigens in the majority of animals with seizures. After the animals have recovered from the acute phase at 8 weeks, the MHC class II expression has largely disappeared from the substantia nigra but MHC class II–expressing microglia are found in the dorsal hippocampus of those rats with loss of cells from CA1. These results show that microglia are responsive to abnormal electrical activity in the central nervous system in the absence of degenerative changes. Further studies are required to determine how microglia may contribute to the neuropathology of epilepsy.
Detection of numerical chromosome aberrations in brain tumours by fluorescence in situ hybridization on smear preparations of small tumour biopsies
Authors: Löw M. , Feiden W. , Moringlanet J. R. , Zang K. D. , Henn W.
Published: May 2008

We present a technique for the preparation and interphase cytogenetic analysis of native tumour cell nuclei from smear preparations of small biopsies of human brain tumours. The presence of tumour–specific numerical chromosome aberrations can be determined by fluorescence in situ hybridization (FISH) analysis using chromosome–specific repetitive DNA probes. The FISH analysis of smear preparations provides cytogenetic information about brain tumour samples, within 2 days, avoiding time–consuming and artefact–prone tumour cell culture.
Transferrin receptors in the normal human hippocampus and in Alzheimer's disease
Authors: Morris C. M. , Candy J. M. , Kerwin J. M. , Edwardson J. A.
Published: May 2008

Several lines of evidence suggest that aluminium may play a role in the pathogenesis of Alzheimer's disease (AD). The iron transport protein transferrin is the major transport protein for aluminium, and aluminium gains access to cells by means of a specific cell surface transferrin receptor. We have assessed the distribution of transferrin receptors in the normal and AD hippocampal formation using [3H]–transferrin ([3H]–Tf) binding and tritium film autoradiography, in order to assess the role of the transferrin receptor in AD. In normal brain, 3H]–Tf binding was highest in the pyramidal cell layers with CA2> dentate gyrus granule cell layer ≥Cal >CA3 ≥ CA4>subiculum>parahippocampal gyrus. In AD, significant reductions in [3H]–Tf binding were found in CA1, CA2 and CA4 pyramidal cell layers. The reduced [3H]–Tf binding in AD may, however, be due to poor pre–mortem agonal states which correlated with reduced [3H]–Tf binding. The discrepancy between the distribution of transferrin receptors in the hippocampus and those areas which are prone to the formation of senile plaques and neurofibrillary tangles suggests that if transferrin–mediated uptake of aluminium in AD/SDAT is significant in the pathogenesis of this disorder, it is not the only determinant of Alzheimer–type neuropathology.
Parvalbumin immunohistochemistry in denervated skeletal muscle
Authors: Olive M. , Ferrer I.
Published: May 2008

Parvalbumin is a calcium–binding protein which, in muscle, is mainly found in type 2B fibres, whereas type 1 fibres lack parvalbumin immunoreactivity. Previous studies have shown that this pattern is highly dependent upon motor neuron innervation and is modified in denervated, cross–reinnervated or chronic low–frequency stimulated muscles. In the present study, we have examined the modifications of parvalbumin immunocyto–chemistry in the anterior tibialis muscle of the rat at different intervals following section of the sciatic nerve. During the first 2 weeks after denervation, no changes in parvalbumin immunoreactivity were seen, although a global reduction of fibre diameter was observed. Three weeks after denervation, small angulated. strongly parvalbumin–immunoreactive fibres appeared. From the second month onwards, the pattern of parvalbumin immunohistochemistry was characterized by areas composed of small, strongly immunoreactive fibres separated by less atrophic areas displaying a normal chequerboard distribution of parvalbumin immunoreactivity. The increase of parvalbumin–immunoreactivity in denervated and reinnervated muscle, as seen in our study, indicates that important changes in parvalbumin distribution occurs in muscle fibres after denervation. These changes are probably produced in an attempt to bind the free cytosolic calcium which accumulates in denervated fibres, and further reinforces the role of parvalbumin in calcium homeostasis during denervation and reinnervation.
Morphogenesis of amyloid plaques in 87V murine scrapie†
Authors: Jeffrey M. , Goodsir C. M. , Bruce M. E. , McBride P. A. , Farquhar C.
Published: May 2008

Amyloid plaques of scrapie–infected mouse brains are composed of fibrillar forms of a host coded, cell surface sialoglycoprotein called PrP (prion protein). Serial ultrastructural immunogold staining was performed on plaques identified by light microscopic immunocytochemistry of brains of VM mice infected with the 8 7V strain of scrapie. Classical plaques, of a kuru–type morphology, were composed of a central core of bundles of amyloid fibrils. Amyloid fibrils of classical plaques were immunoreactive for PrP. In addition, PrP was also found at the plaque periphery, in the absence of fibrils, at the plasmalemma of cell processes and in the associated extracellular spaces. Frequent microglial cells and occasional astrocytes contained PrP within lysosomes. Other plaques with few or no recognizable amyloid fibrils were frequent and were termed primitive plaques. PrP could be demonstrated in a non–fibrillar form at the plasmalemma and in the extracellular spaces between neurites of such plaques. Many primitive plaques showed little or no sub–cellular pathology associated with the PrP accumulation. PrP was closely associated with the plasma–lemma of occasional dendrites passing towards the centre of primitive plaques. These results suggest that plaques are formed around one or more PrP releasing dendrites. PrP accumulates in the extracellular spaces adjacent to such processes prior to its spontaneous aggregation into fibrils. Lysosomal accumulation of PrP in microglia and astrocytes located at the periphery of plaques suggest that these cells are involved in the phagocytosis of excess or abnormal PrP.
The nasal route of cerebrospinal fluid drainage in man. A light–microscope study
Authors: Löwhagen P. , Johansson B. B. , Nordborg C.
Published: May 2008

The drainage routes from the subarachnoid space to the nasal mucosa were investigated in autopsy material. Indian ink, applied post–mortem to the olfactory groove, promptly filled the perineurial spaces around the olfactory nerve branches in the dura, the lamina cribrosa and the submucosal tissue in the nose. In a case of recent subarachnoid haemorrhage, the perineurial spaces even around the most distal olfactory nerve branches were congested with blood and there was an abundant accumulation of red corpuscles in the apical part of the nasal mucosa. Iron–containing pigment was found in the perineurial spaces of proximal and distal olfactory nerve branches as well as in the nasal mucosal stroma in cases with older haemorrhagic lesions. The findings show that the perineurial spaces provide an efficient drainage route from the subarachnoid space to the nasal mucosa in cases with haemorrhagic cerebral lesions. A complementary drainage route for the cerebrospinal fluid was indicated by the presence of indian ink, red corpuscles and iron pigment in arachnoid villi, which penetrated the lamina cribrosa and ended in the nasal submucosal tissue. Iron in the deep cervical lymph nodes should not be taken as evidence of transport from the CNS, since iron pigment was also found in cases without intracranial haemorrhage.
In situhybridization in neuropathology
Authors: Woodroofe M. N. , Cuzner M. L. , Ironside J. W.
Published: May 2008

In situhybridization (ISH) allows the demonstration and localization of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in tissue sections, cells and chromosomes by utilizing a specific interaction with a labelled nucleotide probe of known composition. Although this technique has been employed for many years using radiolabelled probes, the recent development of non–isotopic labelling systems and the greatly increased availability of synthetic nucleic acids has allowed an enormous expansion in the potential applications of ISH. The technique is now applicable to unfixed and fixed tissues, including archival material. The use of enzyme–linked antibody techniques to detect labelled probes has greatly increased the sensitivity of non–isotopic ISH without a loss of specificity. The successful use of ISH demands careful selection of labelled probes, adequate tissue pretreatment to allow access of the probe, control of the stringency of probe binding and a sensitive reporter system, in addition to adequate controls. The accurate localization of nucleotides in the central nervous system (CNS) has many current research applications in the study of gene expression in multiple sclerosis and other inflammatory disorders, and a wide range of neurodegenerative disorders, viral infections and neoplasms. The technique is of diagnostic value in viral disorders, particularly where multiple infections occur. The combination of non–isotopic ISH with immuno–cytochemistry, electron microscopy and quantitative image analysis greatly increases its research potential, while the development of a related method, thein situpolymerase chain reaction, offers an additional opportunity for further enhancing the sensitivity of this technique.
Neuropathological changes following occlusion of the superior sagittal sinus and cerebral veins in the cat
Authors: Cervós‐Navarro J. , Kannuki S. , Matsumoto K.
Published: May 2008

Superior sagittal sinuses (SSS) of 36 mongrel cats were occluded by polymer injection. Immediately prior to the occlusion, Evans–blue (EB) was administered intravenously. The cats were killed 1, 3, 6, 12, 24, 72 and 120 h after sinus occlusion. Two sham–operated cats were killed 6 h and two 120 h after the operation. In 16 cats in which the occlusion was limited to the SSS, as well as in the sham–operated cats, no EB extravasation was present. However, ultrastructurally in two animals, the extracellular spaces were moderately enlarged, corresponding to increased permeability for water without opening of the BBB for proteins. In 20 cats in which cortical veins were occluded, in addition to the SSS, EB was extravasated. In nine of these cats, which had moderate oedema, EB–staining was present only in the cortex. In 11 cats with severe oedema, massive EB extravasation was observed also in the white matter. The U–fibre layer was free of EB, suggesting that the extension of oedema was blocked by this zone. Cats with severe edema showed extensive haemorrhagic cerebral infarction widely, but not completely, overlapping with ischaemic necrosis, and corresponding to the differences in the territories of arterial supply and of venous drainage. Seven animals displayed haematomas in the parasagittal white matter. Electron microscopy (EM) showed damage to the endothelium of capillaries and venules with extravasation of platelets. In cats which survived longer than 24 h, the extracellular spaces were filled with proteinaceous transudate. Gliosis of the affected grey and white matter was observed in cats examined 24, 72 and 120 h after occlusion. Notwithstanding the differences between this model and human cerebral sinus and vein thrombosis, the procedure represents an experimental approach to understanding the variability of the clinical course in patients with thrombosis of SSS. The results stress the role of the occlusion of the cortical veins in the extension of brain damage.
Interactions between fetal rat brain cells and mature brain tissue in vivo and in vitro
Authors: Marienhagen K. , Pedersen P.‐H. , Terzis A. J. A. , Laerum O. D. , Arnold H. , Bjerkvig R.
Published: May 2008

Fetal as well as mature neural cells were homografted into the right cerebral hemisphere of adult BD–IX rats. The animals were sacrificed 7 d after implantation, and the localization of implanted cells was visualized by fluorescence and light microscopy. The cell implants were prestained with the fluorescent vital dye 1,1′‐Dioctadecyl –3,3,3′3′‐tetramethylindocarbocyanine perchlorate (Dil) to discriminate between implanted cells and host brain tissue. At the implantation site, the fetal brain cells as well as the cells from immature brain cell aggregates showed diffuse infiltration into the surrounding host brain tissue of up to 0.5 mm. Extensive cell migration along the corpus callosum for up to 5 mm in the coronal and to a lesser extent in the sagittal plane was also observed. In addition, fetal cells were distributed in the subarachnoid space of both cerebral hemispheres and showed a distinct association with larger blood vessels. Cells from mature brain aggregates did not migrate as far as fetal cells and showed only a local infiltration into the host neuropil. Fluorescent microspheres as well as fixed fetal brain cells were implanted, either alone or in combination with vital cells to distin guish between active cell migration and passive cell displacement. The microspheres and the fixed cells were found either localized to the implantation pathway or distributed in the corpus callosum for up to 2 mm in the coronal plane without any dispersion in the sagittal plane. The microspheres also showed an extensive displacement in the subarachnoid space. In vitro co–culture experiments between two immature aggregates showed a complete fusion of the two aggregates during a 96 h culture period. In co–cultures between two mature aggregates complete fusion was not prominent, although the confrontation zone appeared diffuse. Confrontations between a mature and an immature aggregate showed the same pattern of interaction as seen for the two mature aggregates. It is concluded that carbocyanine dyes may be used as a tracer for transplanted cells. Cells from fetal rat brain cell aggregates, opposed to those from mature aggregates, showed extensive migration along well defined anatomical structures in the mature brain. Some of the spread of cells following implantation is probably due to passive movement since inert microspheres will spread into certain areas of the CNS.
Reactive cell proliferation and microglia following injury to the rat brain
Authors: Giordana M. T. , Attanasio A. , Cavalla P. , Migheli A. , Vigliani M. C. , Schiffer D.
Published: May 2008

The non–astrocytic cells which proliferate in the rat brain after the induction of an area of necrosis have been characterized and counted by means of combined in vivo bromodeoxyuridine (BrdU) administration and immuno–histochemical demonstration of glial fibrillary acid protein (GFAP), vimentin, Ricinus communis agglutinin 120 (RCA–1), Griffonia simplicifolia B4 isolectin (GSI–B4), keratan sulphate (KS), carbonic anhydrase C (CA.C), transferrin (TF) and ferritin. Two days after the injury, 7.5% of the proliferating cells were GFAP–positive reactive astrocytes, 5.7% were RCA–1–positive cells and 17.4% were GSI–B4–positive cells. Lectin–binding cells had the microscopic and ultrastructural aspects of microglia; they proliferated around the needle track and in the corpus callosum. Microglia represented a large fraction of the proliferating cells. Evidence is presented for the origin of at least a proportion of perilesional astrocytes and microglia from the periventricular matrix, and of microglia from blood precursors. Other non–proliferating microglia cells transiently appeared in the normal brain around the wound, in agreement with the existence of two different microglia cell populations reacting with different modalities to an area of necrosis.
Cell counts in the substantia nigra: a comparison of single section counts and disector counts in patients with Parkinson's disease and in controls
Authors: Ma S. Y. , Collan Y. , Röyttä M. , Rinne J. O. , Rinne U. K.
Published: May 2008

The disector (DS) is a method by which it is possible to estimate the density of cells in a volume of tissue, and when associated with Cavalieri's principle. the total number of cells of a neural nucleus. Since the introduction of this method, there has been some uncertainty about the value of cell counts estimated using single section (SS). To compare these two methods, we counted the pigmented neurons in the pars compacta of the substantia nigra (SNpc) in seven normal controls and in four patients with Parkinson's disease (PD), using both single histological sections and the DS. The calculations were performed at two different levels of the substantia nigra. Level I was cut through the colliculus superior and caudal red nucleus, and level II showed the exit of the third cranial nerve in all cases. As methods, the two counts were in close agreement (Pearson's correlation coenicient at levels I and II were r=0.97 and r=1.00, respectively, P<0.001). The correspondence was different in the controls and in the parkinsonian patients, however, as can be judged from the slopes of the average regression lines (0.20 for controls, 0.31 for parkinsonian patients). It is nevertheless evident that once the regression line has been defined, DS counts can be estimated Gom SS counts when the pigmented neuron numbers are counted in the SNpc. The results suggest that comparisons of pigmented neuron counts made from SS are relevant if the cutting level of the section is well defined, and if section thickness is kept constant.
The cortical neuritic pathology of Huntington's disease
Authors: Jackson M. , Gentleman S. , Lennox G. , Ward L. , Gray T. , Randall K. , Morrell K. , Lowe J.
Published: May 2008

We have studied the brains of 10 patients with clinically and pathologically defined Huntington's disease and graded the degree of striatal pathology according to the Vonsattel grading system. Sections from nine cerebral cortical areas (Brodmann areas 8. 10, 24, 33, 28, 38, 7, 39, 18), the cerebellum, hypothalamus, medulla and caudate nucleus were stained with antibodies to ubiquitin and ubiquitin C‐terminal hydrolase (PGP 9.5). Dystrophic neurites. immunoreactive with ubiquitin and PGP 9.5 were detected in all cortical areas. in layers 3, 5 and 6, of all brains studied. No dystrophic neurites were found in subcortical areas or cerebellum. Sections from cortical areas 8 and 24 from the two brains with the most and least ubiquitin‐immunoreactive neurites were stained with antibodies to β‐amyloid precursor protein, tau, glial fibrillary acidic protein, neurofilament protein, αB crystallin, GABA, cholecystokinin and somatostatin. The dystrophic neurites were found to also react with β‐amyloid precursor protein. Electron microscopy showed the abnormal neurites to contain granulo‐filamentous material. Granular deposits with a diameter of 40–100 nm were interspersed between randomly orientated ‘fuzzy’ or coated, straight or slightlv curved filaments measuring 10–15 nm in diameter. These structures have not been seen in control brain and differ from age‐related neuritic degeneration and neurites associated with amyloid. Immunohistochemically these structures most resemble CA 2/3 neurites seen in Lewy body disease, and, ultrastructurally, the intraneuronal filamentous inclusions in motor neuron disease. The areal density of these neurites was quantified in 20 microscopic fields in the superior frontal and anterior cingulate sections (Brodmann areas 8 and 24) and did not correlate with the Vonsattel grade, suggesting that they are an independent and possibly primary cortical pathology in Huntington's disease.
Accumulation of hippocampal cholinergic neurostimulating peptide (HCNP)‐related components in Hirano bodies
Authors: Mitake S. , Ojika K. , Katada E. , Otsuka Y. , Matsukaw N. , Fujimori O.
Published: May 2008

We have previously isolated from the hippocampus of young rats a novel peptide termed ‘hippocampal cholinergic neurostimulating peptide’ (HCNP) which specifically enhances the cholinergic activity of the septohippocampal system in vitro. Cloning and base sequence analysis of HCNP‐specific cDNA from rat and human cDNA libraries revealed that the 1.1 kDa peptide aligns at the N‐terminal region of its 21 kDa precursor protein. An affinity‐purified rabbit antibody to rat HCNP prepared by us recognizes the C‐terminal domain of the peptide. while an antibody against human HCNP binds to a large portion of the peptide. In this report we show that both antibodies react with HCNP‐related components present in the soluble cytosol fraction of human brain tissue.

Immunohistochemical examination of human nervous system tissues from elderly individuals revealed that Hirano bodies in Sommer's sector of the hippocampus were specifically stained by anti‐HCNP antibodies. The number of HCNP‐positive Hirano bodies was greater in patients with Alzheimer's disease than in normal, age‐matched individuals. The immunohistochemical results were substantiated by immunoelectron microscopy. The present findings indicate that HCNP‐related components accumulate in Hirano bodies, suggesting that patients who bear these inclusions may have a disturbance of the septohippocampal cholinergic system, considered to be of importance for learning and memory formation.
Characterization of perivascular cells in astrocytic tumours and peritumoral oedematous brain
Authors: Kida S. , Ellison D. W. , Steart P. V. , Weller R. O.
Published: May 2008

Perivascular cells (PVCs) form an immunophenotypically defined population that plays an important scavenging role in the perivascular fluid drainage pathways in the rat brain: such cells may also act as antigen‐presenting cells. The present study tests the hypotheses that (a) PVCs in human brain are distinct from microglia and haematogenous macrophages, and (b) PVCs within astrocytic tumours and peritumoral oedematous brain tissue react in a similar way to PVCs in the rat brain. Parafin sections of formalin‐fixed tissue from 10 astrocytomas. 10 anaplastic astrocytomas, 10 glioblastoma multiforme. peritumoral oedematous brain and from normal human brain were examined immuno‐cytochemically using antibodies HLA‐DR P‐chain for MHC class II antigen, PGMl and MAC 387 directed against macrophage components, MT1 for T lymphocytes and GFAP for astrocytes. No PVCs, microglia or macrophages were labelled by these techniques in paraffin sections of normal brain. Microglia. Macrophages recently derived from haematogenous monocytes and PVCs were labelled by immunocytochemistry in all tumours but were more numerous in glioblastomas than in astrocytomas or anaplastic astrocytomas. Perivascular cells were distinguished by their perivascular position, their expression of MHC class II antigen and were labelled by PGM1 antibody but not by MAC 387 antibody. Microglia and monocyte/macrophages, remote from blood vessels, on the other hand, were strongly labelled by MAC 387, moderately by PGMl and showed weak expression of MHC class II antigen. A similar pattern of staining was seen in peritumoral oedematous tissue. These findings suggest that PVCs form a defined population of resident cells in the human brain and that they are distinct from microglia, monocytes and macrophages. Furthermore. upregulation of MHC class II and PGM1 expression on PVCs in tumours and oedematous brain, suggest that they play a similar scavenging role in the human brain to that seen in the rat brain.
Single strand conformation analysis of two genes contained within the first intron of the neurof ibromatosis type I gene in patients with multiple sclerosis
Authors: Hinks L. J. , Price S. E. , Mason C. R. , Thompson R. J.
Published: May 2008

Single strand conformation analysis has become the most widely used technique to screen large numbers of DNA samples for unknown mutations which may contribute to genetic susceptibility to disease. The method relies on the electrophoretic migration of a single strand of nucleic acid in a polyacrylamide gel being dependent on its conformation which is in turn dependent on its sequence. We have examined two closely related genes present in the first intron of the neurofibromatosis type I gene — the oligodendrocyte myelin glycoprotein (OMGP) gene and the ecotropic viral integration 2A (EVI2A) gene — in 36 patients with multiple sclerosis (MS) and 36 healthy controls. A single mutation was found in the OMGP gene which resulted in an amino acid change of glycine to aspartic acid. This occurred in identical proportions (16.6%) in MS patients and controls. Two rare mutations were found in the EVI2A gene, one resulting in an arginine substituting for a glutamine (one control and one patient), the other in the replacement of a glycine with serine (one control only). A third common polymorphism was seen in 5′‐untranslated region of the EVIZA gene, with 65% of patients and controls showing a T→C transition in either a heterozygous or a homozygous form. This makes it unlikely that either of these genes is involved in genetic susceptibility to MS, but regions of these genes outside of the exonic sequences have not been examined.
Experimental herpes simplex virus type 1 (HSV‐1) infection of the spinal cord and dorsal root ganglia
Authors: Wharton S. B. , Meyers N. L. , Nash A. A.
Published: May 2008

Host factors determining the outcome of herpes simplex virus type 1 (HSV‐1) infection within neurons are poorly understood. This paper aims to identify regional differences in the behaviour of HSV‐1 within the nervous system as an approach to investigating the role of the host environment in determining the outcome of infection. We describe a mouse model of HSV infection focused on motor neurons of the spinal cord, resulting from intramuscular injection (i.m.) and compare this with the behaviour of virus within sensory neurons following scarification of virus on to skin. Viral antigen was detectable immunohistochemically by 2 days in both models and disappeared by 9–11 days. The time course of acute infection was reflected in the i.m. group by quantitative plaque assay for virus. Inflammation and cell destruction occurred in both models, but clinical features and histological destruction were greater in the group infected via the intramuscular route. In the sensory ganglia, a latent state from which virus could be reactivated by explanation, was established with LATS expression detectable in many neurons at 3 5 days post infection (pi.), but not in non‐neuronal cells. Expression of latency associated transcript (LATS) was detected in motor neutrons in spinal cords at 35 days p.i. providing evidence for establishment of a LATS‐positive latent state at this site, and continued to be detectable up to 6 months post‐infection. In addition, LATS was detected in white matter at late times, suggesting a non‐neuronal site of latency. In contrast to the behaviour in sensory ganglia, induced reactivation from spinal cords, by explanation and nerve section, was a very rare event. We have shown that a LATS‐positive latent state can be established within motor neurons of the CNS, but that there are regional differences in the biology and outcome of infection between the CNS and peripheral nervous system. We propose that this may be a useful model to study reproducibly, the behaviour of HSV‐1 in a CNS environment and, by comparison with sensory ganglion infection, to explore host factors which may underlie these regional differences. The relevance of this model for using HSV‐1 as a therapeutic vector for motor neurons is also discussed.
X‐ray microprobe analysis of corpora amylacea
Authors: Tokutake S. , Nagase H. , Morisaki S. , Oyanagi S.
Published: May 2008

Since corpora amylacea is concentrated in the high density fraction in the subcellular fractionation of autopsy brain, it is suspected that inorganic materials accumulate in corpora amylacea. Therefore, elemental analyses of partially purified corpora amylacea from autopsy brain from a patient with Alzheimer's disease and those from brain of a non‐demented patient were performed by the X‐ray microprobe method. Prominent peaks of sodium, phosphorus, sulphur and chloride were observed, and mapping analyses confirmed that these elements were actually contained within the corpora amylacea. A similar result was obtained using cryostat sections. Corpora amylacea are characteristically distributed along the margin of blood vessels, beneath the pial border of the hippocampus and in the subependymal zones of ventricles of aged brains, namely in the vicinity of blood and cerebrospinal fluid. From this distribution and from the results of the present paper, we suggest that corpora amylacea play a role in the absorption and accumulation of inorganic materials which have been extravasated from blood and cerebrospinal fluid (CSF) and taken up by astrocytes. This may reflect alteration of the blood‐brain and blood‐CSF barriers in the ageing brain.
Reactive microglia in cerebral ischaemia: an early mediator of tissue damage?
Authors: Gehrmann J. , Banati R.B. , Wiessnert C. , Hossmann K.‐A. , Kreutzberg G.W.
Published: May 2008

Microglial cell activation is a rapidly occurring cellular response to cerebral ischaemia. Microglia proliferate, are recruited to the site of lesion, npregulate the expression of several surface molecules including major histocom‐patibility complex class I and II antigens, complement receptor and the amyloid precursor protein (APP) as well as newly expressed cytokines, e.g. interleukin‐1 and transforming growth factor pl. The ischaemia‐induced production of APP may contribute to amyloid deposition in the aged brain under conditions of hypofusion. Ultra‐structurally, microglia transform into phagocytes removing necrotic neurons but still respecting the integrity of eventually surviving neurons even in the close vicinity of necrotic neurons. Microglial activation starts within a few minutes after ischaemia and thus precedes the morphologically detectable neuronal damage. It additionally involves a transient generalized response within the first 24 hours post‐ischaemia even at sites without eventual neuronal cell death. In functional terms, the microglial reaction appears to be a double‐edged sword in ischaemia. Activated microglia may exert a cytotoxic effector function by releasing reactive oxygen species, nitric oxide, proteinases or inflammatory cytokines. All of these cytotoxic compounds may cause bystander damage following ischaemia. Pharmacological suppression of microglial activation after ischaemia has accordingly attenuated the extent of cell death and tissue damage. However, activated microglia support tissue repair by secreting factors such as transforming growth factor βl which may limit tissue damage as well as suppress astroglial scar formation. In line with ultrastructural observations microglial activation in ischaemia is a strictly controlled event. By secreting cytokines and growth factors activated microglia most likely serve seemingly opposed functions in ischaemia, i.e. maintenance as well as removal of injured neurons. Post‐ischaemic pharmacological modulation of microglial intervention in the cascade of events that lead to neuronal necrosis may help to improve the structural and functional outcome following CNS ischaemia.
Single section and disector counts in evaluating neuronal loss from the substantia nigra in patients with Parkinson's disease
Authors: Ma S. Y. , Röytta M. , Rinne J. O. , Collan Y. , Rinne U. K.
Published: May 2008

In order to investigate the correlation between single section (SS) and disector (DS) counts for estimating the pigmented neurons in the pars compacta of the substantia nigra (SNpc), 12 patients with Parkinson's disease (PD) and seven controls were studied. The SS counts were obtained at the level of the exit of the third cranial nerve in the SNpc. The DS counts were made from the whole volume of the SNpc. There was a significant correlation between SS and DS counts (r=0.94, P<0.001), suggesting that the methods closely agree. Comparison of SS and DS counts in controls and PD patients showed that the pigmented neurons in PD were decreased by 75% (P<0.001) and 55% (P<0.001) in the SS and DS counts, respectively. This study suggests that loss of pigmented neurons from the SNpc in PD can be estimated by either method.
p53 allelic imbalance in astrocytoma detected using fluorescent PCR of microsatellite repeat polymorphisms
Authors: Al‐Sarraj S. , Bridges L. R. , Cawkwell L. , Lewis F. A. , Quirke P.
Published: May 2008

Previous reports have shown that p53 gene alteration plays an important role in tumourigenesis. Allelic loss of 17p in astrocytomas was detected in previous studies by restriction fragment length polymorphisms (RFLP). In this study we have analysed 47 cases of astrocytic tumours (26 glioblastomas [grade IV], 11 anaplastic astrocytomas [grade III], seven fibrillary astroctyomas [grade II] and three pilocytic astrocytomas [grade I]) for the presence of allelic imbalance at the p53 gene locus using intragenic markers. We used an informative method based on microsatellite polymorphisms at the p53 gene locus and fluorescent PCR. The fluorescently‐labelled PCR products were then detected and analysed using an automated DNA sequencer with appropriate software. Seven of 47 (14.9%) cases were homozygous (uninformative). Five of the remaining 40 cases (12.5%) showed allelic imbalance at the p53 locus (three ana‐plastic astrocytomas [grade III] and two glioblastomas [grade IV]). None of the fibriIlary astrocytomas (grade II) or pilocytic astrocytomas (grade I) showed allelic imbalance at the p53 locus. These results suggest that allelic imbalance at the p53 locus is not frequent and when it does occur is in high grade tumours.
Superoxide anions in the pathogenesis of talc‐induced cerebraI vasocontraction
Authors: Mori T. , Nagata K. , Matsuit T. , Ishida T. , Ohami H. , Asano T.
Published: May 2008

We have recently reported that sustained contraction of the canine basilar artery induced by the intrathecal injection of talc (crystallized hydrous magnesium silicate) mimicked delayed vasospasm following subarach‐noid haemorrhage. The present study aims to examine the pathomechanism underlying talc‐induced vasocontraction. from the viewpoint of free radical theory, which has been established as a cause of delayed vasospasm. We estimated the effects of a prolonged intrathecal infusion of human recombinant Cu/Zn superoxide dismutase (hr SOD) on the contraction of the basilar artery caused by the intrathecal injection of talc in beagle dogs. which were assigned to the three groups: G1. sham operation with saline treatment: G2, talc injection with saline treatment; and G3, talc injection with 2 ml of hr SOD (7 × 104 Uiml) treatment. Talc administration resulted in the reduction in the angio‐graphic calibre of the basilar artery by 63 and 61% on days 3 and 7 (G2). The treatment with hr SOD (G3) led to a significant attenuation of talc‐induced contraction of the basilar artery on days 3 (P<0.05 vs. G2) and 7 (P<0.05 vs. G2). In the basilar artery wall of days 3 and 7 in G2. pathological changes such as myonecrosis, cytoplasmic vacuolation and detached intercellular junctions were observed. However, these pathological changes almost disappeared in G3. The present findings suggest that superoxide anions may initiate and/or mediate talc‐induced vasocontraction and subsequent structural damage of the basilar artery.
Experimental induction of corpora amylacea‐like inclusions in rat astroglia
Authors: Cissé S. , Schipper H. M.
Published: May 2008

Corpora amylacea (CA) are glycoproteinaceous inclusions that accumulate in the human central nervous system during normal ageing, and to an even greater extent in Alzheimer's disease and other neurodegenera‐tive disorders. They are particularly prominent in subpial and subependymal regions, and are most commonly located within astrocytes and their processes. We previously demonstrated that human CA share many tinctorial and histochemical properties in common with Gomori‐positive cytoplasmic granules which accumulate in periventricular astrocytes of the ageing vertebrate brain and in rat astroglial cultures exposed to the sulphydryl agent, cysteamine (CSH). In the present study, long‐term exposure of neonatal rat astrocyte cultures to CSH resulted in the formation of large spherical, PAS‐positive cytoplasmic inclusions which are highly reminiscent of, if not identical to, human CA.

As in the case of human CA and Gomori‐positive astrocyte granules, the CSH‐induced CA‐like inclusions exhibit non‐enzymatic peroxidase activity and consistent immunolabelling with antibodies directed against the mitochondrial protein, sulphite oxidase. Taken together, our findings suggest that progressive mitochondrial damage and macroautophagy play an important role in the biogenesis of CA (and Gomori‐positive granules) in astrocytes of the ageing periventricular brain.
Increase of mitochondria in vasa nervorum of cases with mitochondrial myopathy, Kearns‐Sayre syndrome, progressive externaI ophthalmoplegia and MEWS*
Authors: Molnar M. , Neudecker S. , Schröder J. M.
Published: May 2008

Previous studies on patients with mitochondrial myopathy, encephalopathy. lactic acidosis, and stroke‐like episodes (MELAS) revealed accumulations of mitochondria in endothelial cells. smooth muscle cells of pial arterioles, and small intracerebral arteries up to 250μm in diameter; in pericytes of capillaries, endothelial cells, and smooth muscle cells of small blood vessels in skeletal muscle; and according to preliminary results also in endothelial and smooth muscle cells of capillaries and arterioles in sural nerves. These mitochondria do not show the prominent paracrystalline inclusions which are seen in striated muscle fibres and led to the identification of this group of disorders. To corroborate our preliminary findings in peripheral nerves, additional cases have been evaluated morphometrically by electron microscopy including cases in which rnitochondrial DNA (mtDNA) mutations have been identified. In fact, an increase of the mean number and an enlargement of the mean cross‐sectional area of mitochondria was noted in endothelial and smooth muscle cells of endoneurial and epineurial arterioles, and in endothelial cells and in pericytes of capillaries in sural nerves of the 20 cases with mitochondrial disorders studied. This increase was statistically significant compared to the control group. However, due to heteroplasmia, which is a common feature in mitochondrial disorders, and because of the limited number of measurable blood vessels and cases, no significant differences could be detected between the various types of mitochondrial diseases which were characterized by dflerent point mutations or deletions of mtDNA. Our findings suggest that the mitochondria play a significant role in the pathogenesis not only of myopathic and encephalopathic symptoms, but also in the pathogenesis of peripheral neuropathy which appears to be regularly associated with mitochondrial disorders.