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J E Galvin

Publications and source records attributed to J E Galvin.

At least 19 recordsLinked to original sources

Effects of a gamma-secretase inhibitor in a randomized study of patients with Alzheimer disease.

LY450139 dihydrate, a gamma-secretase inhibitor, was studied in a randomized, controlled trial of 70 patients with Alzheimer disease. Subjects were given 30 mg for 1 week followed by 40 mg for 5 weeks. Treatment was well tolerated. Abeta(1-40) in plasma decreased by 38.2%; in CSF, Abeta(1-40) decreased by 4.42 +/- 9.55% (p = not significant). Higher drug doses may result in additional decreases in plasma Abeta concentrations and a measurable decrease in CSF Abeta.

Alanine↗

The AD8: a brief informant interview to detect dementia.

BACKGROUND: Brief measures that accurately discriminate normal cognitive aging from very mild dementia are lacking. Cognitive tests often are insensitive to very mild dementia. Informant-based measures may be more sensitive in detecting early dementia. OBJECTIVE: To identify informant-reported clinical variables that differentiate cognitively normal individuals from those with very mild dementia. METHODS: A 55-item battery of informant queries regarding an individual's cognitive status was derived from a semistructured interview and a consensus panel of dementia experts. The battery was evaluated with informants for 189 consecutive participants of a longitudinal study of memory and aging and compared with an independently obtained Clinical Dementia Rating (CDR) score for the participant. Multiple regression and receiver operator characteristic curves assessed subsets of the items to discriminate between CDR 0 (no dementia) and CDR 0.5 (very mild dementia). RESULTS: The final version (AD8) querying memory, orientation, judgment, and function was administered to an additional sample of 112 CDR 0 and 68 CDR 0.5 participants. Using a cut-off of two items endorsed, the area under the curve was 0.834, suggesting good to excellent discrimination, sensitivity was 74%, and specificity was 86% (prevalence of 0.38 for very mild dementia). Inclusion of 56 additional individuals with mild to severe dementia (increasing dementia prevalence to 0.53) increased sensitivity to 85%. CONCLUSIONS: The AD8 is a brief, sensitive measure that reliably differentiates between nondemented and demented individuals. Use of the AD8 in conjunction with a brief assessment of the participant could improve diagnostic accuracy in general practice.

Aged↗

The pathology of the substantia nigra in Alzheimer disease with extrapyramidal signs.

BACKGROUND: Extrapyramidal signs (EPS) are common in Alzheimer disease (AD) and increase in prevalence as AD advances. The neuropathologic substrate responsible for EPS in AD remains to be fully characterized. METHODS: Subjects had a clinical diagnosis of AD confirmed by neuropathologic examination. EPS during life were documented by clinical methods assessing bradykinesia, cogwheel rigidity, rest tremor, and parkinsonian gait. Subjects with EPS and previous neuroleptic exposure were excluded. Twenty-eight subjects were in the EPS group and 104 subjects were without EPS. Neuron loss, alpha-synuclein (ASYN)-labeled pathology, and tau-labeled pathology in the substantia nigra were measured using semiquantitative techniques such that higher scores represented increased pathologic burden. RESULTS: Presence of nigral ASYN-labeled pathology was more common (50 vs 28.9%; p < 0.05) in the EPS group than in those without EPS. There was more nigral neuron loss in the EPS group (1.50 vs 1.11 in no-EPS group; p < 0.05). Tau-labeled burden was not different by group comparisons; however, EPS onset at later stages of dementia severity was associated with increased tau-labeled pathology (Kendall tau-B = 0.48, p < 0.01) and this association remained after controlling for dementia severity at death. Additionally, moderate to severe tau burden was more common in the subgroup with "pure AD" (definite AD without other neuropathology) with EPS (81.8%) than cases without EPS (49.0%; p < 0.05). Four subjects with EPS (14.3%) had little to no significant nigral pathologic changes. CONCLUSIONS: Clinically detected extrapyramidal signs (EPS) in Alzheimer disease (AD) are associated with substantia nigra pathology including alpha-synuclein aggregation, hyperphosphorylated tau accumulation, and neuron loss that may account for the increasing prevalence of EPS as AD progresses. In some cases, limited nigral pathology suggests extranigral factors in the clinical symptoms of EPS.

Aged↗

Familial dementia with Lewy bodies: clinicopathologic analysis of two kindreds.

Familial cases of dementia with Lewy bodies (DLB) are rare. The authors describe two small kindreds with familial DLB: one with pure DLB meeting consensus criteria for DLB and one with coexistent AD pathology that did not fulfill DLB criteria. The authors call attention to the diverse features of DLB and suggest that current clinical criteria may not detect all cases. Familial DLB is clinically heterogeneous and occurs with or without coexistent AD, suggesting the relevance of LB pathology for the developing dementia.

Aged↗

Synucleinopathies: clinical and pathological implications.

The synucleinopathies are a diverse group of neurodegenerative disorders that share a common pathologic lesion composed of aggregates of insoluble alpha-synuclein protein in selectively vulnerable populations of neurons and glia. Growing evidence links the formation of abnormal filamentous aggregates to the onset and progression of clinical symptoms and the degeneration of affected brain regions in neurodegenerative disorders. These disorders may share an enigmatic symmetry, i.e., missense mutations in the gene encoding for the disease protein (alpha-synuclein) cause familial variants of Parkinson disease as well as its hallmark brain lesions, but the same brain lesions also form from the corresponding wild-type brain protein in the more common sporadic varieties of Parkinson disease. It is likely that clarification of this enigmatic symmetry in 1 form of synucleinopathy will have a profound impact on understanding the mechanisms underlying all these disorders. Furthermore, these efforts will likely lead to novel diagnostic and therapeutic strategies in regard to the synucleinopathies.

Animals↗

Pasteurella multocida toxin type D serological assay as an alternative to the toxin neutralisation lethality test in mice.

The objective of this work was to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against Pasteurella multocida toxin type D, that correlated to a mouse lethality test. Currently, the mouse lethality test is one of several tests used world-wide to evaluate serological responses in animals immunised with vaccines containing toxoids. The mouse lethality test involves injecting mice with a mixture of toxin and test serum sample (from animals that have been vaccinated with a toxoid), and then determining antibody titre of the test serum from the number of mice that survive. Thus, the titre calculated is based on the neutralising activity of the test serum. The mouse lethality test requires large numbers of animals and causes severe distress to the animals. Organisations world-wide are working towards alternatives to animals in the development and control of biological products for human and veterinary use. Additionally, the mouse lethality test is labour-intensive, costly and lacks robustness and may be difficult to reproduce between different technicians. We have developed a double sandwich ELISA to measure anti- P. multocida toxoid type D antibodies in swine serum. Sera from swine immunised with vaccines containing type D toxoid showed good correlation to the mouse lethality assay (Spearman analysis=0.94 and Pearson analysis=0.84). When compared to the mouse lethality test, titres obtained using the ELISA format had higher correlation with protective immunity (i.e., lower turbinate atrophy) following challenge with virulent P. multocida. The ELISA assay is more robust, reproducible and costs less than the mouse lethality assay; and it complements efforts to reduce the use of animals in testing.

Animals↗

Differential expression and distribution of alpha-, beta-, and gamma-synuclein in the developing human substantia nigra.

Although the functions of alpha-, beta-, and gamma-synuclein (alphaS, betaS, gammaS, respectively) are unknown, these synaptic proteins are implicated in the pathogenesis of Parkinson's disease (PD) and related disorders. For example, alphaS forms Lewy bodies (LBs) in substantia nigra (SN) neurons of PD. However, since it is not known how these hallmark PD lesions contribute to the degeneration of SN neurons or what the normal function of alphaS is in SN neurons, we studied the developing human SN from 11 weeks gestational age (GA) to 16 years of age using immunohistochemistry and antibodies to alphaS, betaS, gammaS, other synaptic proteins, and tyrosine hydoxylase (TH). SN neurons expressed TH at 11 weeks GA and alphaS, betaS, and gammaS appeared initially at 15, 17, and 18 weeks GA, respectively. These synucleins first appeared in perikarya of SN neurons after synaptophysin, but about the same time as synaptotagmin and synaptobrevin. Redistribution of alphaS from perikarya to processes of SN neurons occurred by 18 weeks GA in parallel with synaptophysin, while betaS and synaptotagmin were redistributed similarly between 20 and 28 weeks GA and this also occurred with gammaS and synaptobrevin between 33 weeks GA and 9 months postnatal. These data suggest that alphaS, betaS, and gammaS may play a functional role in the development and maturation of SN neurons, but it remains to be determined how sequestration of alphaS as LBs in PD contributes to the degeneration of SN neurons.

Adolescent↗

Neurofilament-rich intraneuronal inclusions exacerbate neurodegenerative sequelae of brain trauma in NFH/LacZ transgenic mice.

Several neurodegenerative disorders are characterized by filamentous inclusions in neurons that selectively degenerate. The role these inclusions play in neuron degeneration is unclear, but this issue can be investigated experimentally in relevant animal models. The NFH/LacZ transgenic (TG) mice overexpress the high-molecular-weight neurofilament (NF) subunit (NFH) fused to beta-galactosidase, and these hybrid proteins aggregate into NF-rich, filamentous neuronal cytoplasmic inclusions (NCIs) that have been implicated in the progressive, age-dependent degeneration in subsets of affected neurons. Thus, these TG mice recapitulate some of the key pathology of neurodegenerative disorders with intraneuronal inclusions. To determine if the NCIs compromise neuron survival following traumatic brain injury (TBI), 3- to 6-month old TG and wild-type (WT) mice were subjected to TBI or sham injury. At 2 weeks post-TBI, the TG group showed increased TUNEL staining and activated caspase-3 immunoreactivity in cells of cerebral cortex, adjacent white matter, and hippocampus underlying the injury site, relative to control mice, but this labeling decreased at 4 weeks and was minimal thereafter. Compared to control mice, by 8 weeks postinjury, the TG mice showed a marked decrease in neuron density and increased gliosis in the hippocampal dentate gyrus and CA3 region as well as in the lateral thalamus, while the few remaining CA3 neurons exhibited cytoskeletal alterations, decreased synaptic protein immunoreactivity, and dissolution of NCIs. The more profound long-term neurodegenerative sequelae of TBI in the NFH/LacZ mice compared to WT mice suggest that the presence of intraneuronal inclusions may impair the recovery and long-term viability of injured neurons.

Animals↗

Neurodegeneration with brain iron accumulation, type 1 is characterized by alpha-, beta-, and gamma-synuclein neuropathology.

Neurodegeneration with brain iron accumulation, type 1 (NBIA 1), or Hallervorden-Spatz syndrome, is a rare neurodegenerative disorder characterized clinically by Parkinsonism, cognitive impairment, pseudobulbar features, as well as cerebellar ataxia, and neuropathologically by neuronal loss, gliosis, and iron deposition in the globus pallidus, red nucleus, and substantia nigra. The hallmark pathological lesions of NBIA 1 are axonal spheroids, but Lewy body (LB)-like intraneuronal inclusions, glial inclusions, and rare neurofibrillary tangles also occur. Here we show that there is an accumulation of alpha-synuclein (alphaS) in LB-like inclusions, glial inclusions, and spheroids in the brains of three NBIA 1 patients. Further, beta-synuclein (betaS) and gamma-synuclein (gammaS) immunoreactivity was detected in spheroids but not in LB-like or glial inclusions. Western blot analysis demonstrated high-molecular weight alphaS aggregates in the high-salt-soluble and Triton X-100-insoluble/sodium dodecyl sulfate-soluble fraction of the NBIA 1 brain. Significantly, the levels of alphaS were markedly reduced in the Triton X-100-soluble fractions compared to control brain, and unlike other synucleinopathies, insoluble alphaS did not accumulate in the formic acid-soluble fraction. These findings expand the concept of neurodegenerative synucleinopathies by implicating alphaS, betaS, and gammaS in the pathogenesis of NBIA 1.

Adolescent↗

Molecular analysis of cross-reactive anti-myosin/anti-streptococcal mouse monoclonal antibodies.

Nucleotide sequences of VH- and VL-genes of anti-myosin/anti-streptococcal monoclonal antibodies (mAbs) were analyzed and compared with their highly detailed antigen binding reactivities. Antigen-specificities of the cross-reactive mAbs included myosin, streptococcal M-protein, actin, keratin, N-acetyl-beta-D-glucosamine, vimentin, DNA, tropomyosin, troponin, and laminin as previously described. After nucleotide sequence analysis, homology indicated that some of the V gene sequences aligned with antibodies recognizing gangliosides and blood group antigens glycophorin M and N. Therefore, mAb reactivity with gangliosides and glycophorin M and N was identified. The cross-reactive mAbs utilized a heterogeneous group of germline V-heavy genes comprised of nine J558-, four 7183- and two Q52-family VH-genes. Germline V-light genes utilized by the mAbs included six Vkappa4/5-, three Vkappa8-, two Vkappa10-, three Vkappa19- and one Vkappa23-family VL-genes. No preferential VH/VL-chains correlated with any of the 12 different antigen reactivities, even for mAbs with nearly identical cross-reactivities. However, we did find that the cross-reactive mAb germline genes within a V gene family shared more homology among themselves than with other germline genes within their V gene families, suggesting convergent mutation. Cross-reactive mAbs with the highest relative avidity for myosin were found in the VH7183 family which contained two cytotoxic mAbs. Antibodies with V gene sequences most homologous to those of our cross-reactive anti-myosin/anti-streptococcal mAbs had specificities for laminin, DNA, carbohydrates, or blood group antigens and were reported to cause autoimmune disease in mice.

Amino Acid Sequence↗

Cytotoxic mAb from rheumatic carditis recognizes heart valves and laminin.

Anti-streptococcal antibodies cross-reactive with N-acetyl-betaD-glucosamine (GlcNAc) and myosin are present in the sera of patients with rheumatic fever (RF). However, their role in tissue injury is not clear. In this study, we show that anti-GlcNAc/anti-myosin mAb 3.B6 from a rheumatic carditis patient was cytotoxic for human endothelial cell lines and reacted with human valvular endothelium and underlying basement membrane. Reactivity of mAb 3.B6 with the valve was inhibited by human cardiac myosin > laminin > GlcNAc. The mAb 3.B6 epitopes were localized in fragments of human cardiac myosin, including heavy meromyosin (HMM), the S1 subfragment, and two light meromyosin (LMM) peptides containing amino acid sequences KEALISSLTRGKLTYTQQ (LMM 1) and SERVQLLHSQNTSLINQK (LMM 33). A novel feature of mAb 3.B6 was its reactivity with the extracellular matrix protein laminin, which may explain its reactivity with the valve surface. A laminin A-chain peptide (HTQNT) that includes homology to LMM33 inhibited the reactivity of mAb 3.B6 with human valve. These data support the hypothesis that cross-reactive antibodies in rheumatic carditis cause injury at the endothelium and underlying matrix of the valve.

Acetylglucosamine↗

Axon pathology in Parkinson's disease and Lewy body dementia hippocampus contains alpha-, beta-, and gamma-synuclein.

Pathogenic alpha-synuclein (alphaS) gene mutations occur in rare familial Parkinson's disease (PD) kindreds, and wild-type alphaS is a major component of Lewy bodies (LBs) in sporadic PD, dementia with LBs (DLB), and the LB variant of Alzheimer's disease, but beta-synuclein (betaS) and gamma-synuclein (gammaS) have not yet been implicated in neurological disorders. Here we show that in PD and DLB, but not normal brains, antibodies to alphaS and betaS reveal novel presynaptic axon terminal pathology in the hippocampal dentate, hilar, and CA2/3 regions, whereas antibodies to gammaS detect previously unrecognized axonal spheroid-like lesions in the hippocampal dentate molecular layer. The aggregation of other synaptic proteins and synaptic vesicle-like structures in the alphaS- and betaS-labeled hilar dystrophic neurites suggests that synaptic dysfunction may result from these lesions. Our findings broaden the concept of neurodegenerative "synucleinopathies" by implicating betaS and gammaS, in addition to alphaS, in the onset/progression of PD and DLB.

Axons↗

Increased vulnerability of NFH-LacZ transgenic mouse to traumatic brain injury-induced behavioral deficits and cortical damage.

The authors evaluated the neurobehavioral and neuropathologic sequelae after traumatic brain injury (TBI) in transgenic (TG) mice expressing truncated high molecular weight neurofilament (NF) protein fused to beta-galactosidase (NFH-LacZ), which develop Lewy body-like NF-rich inclusions throughout the CNS. TG mice and their wild-type (WT) littermates were subjected to controlled cortical impact brain injury (TG, n = 19; WT, n = 17) or served as uninjured controls (TG, n = 11; WT, n = 11). During a 3-week period, mice were evaluated with an array of neuromotor function tests including neuroscore, beam balance, and both fast and slow acceleration rotarod. Brain-injured WT and TG mice showed significant motor dysfunction until 15 days and 21 days post-injury, respectively (P<.025). Compared with brain-injured WT mice, brain-injured TG mice had significantly greater motor dysfunction as assessed by neuroscore (P<.01) up to and including 15 days post-injury. Similarly, brain-injured TG mice performed significantly worse than brain-injured WT mice on slow acceleration rotarod at 2, 8, and 15 days post-injury (P<.05), and beam balance over 2 weeks post-injury (P<.01). Histopathologic analysis showed significantly greater tissue loss in the injured hemisphere in TG mice at 4 weeks post-injury (P<.01). Together these data show that NFH-LacZ TG mice are more behaviorally and histologically vulnerable to TBI than WT mice, suggesting that the presence of NF-rich inclusions may exacerbate neuromotor dysfunction and cell death after TBI.

Animals↗

Accumulation of intracellular amyloid-beta peptide (A beta 1-40) in mucopolysaccharidosis brains.

To evaluate whether in vivo accumulations of heparan sulfate caused by inborn errors in the metabolism of glycosaminoglycans lead to the formation of neurofibrillary tangles and/or senile plaques, as seen in Alzheimer disease (AD), we studied postmortem brains from 9 patients, ages 1 to 42 years, with mucopolysaccharidosis (MPS). The brains of patients with Hurler's syndrome (MPS I: n = 5) and Sanfilippo's syndrome (MPS III; n = 4) as well as from caprine MPS IIID and murine MPS VII models were evaluated by thioflavine-S staining and by immunohistochemistry using antibodies directed against heparan sulfate proteoglycans, hyperphosphorylated tau, amyloid-beta peptide precursor proteins (APP), and amyloid-beta peptides (A beta [1-40], and A beta [1-42]). A two-site sandwich enzyme-linked immunosorbent assay (ELISA) was also utilized to compare levels of total soluble and insoluble A beta (1-40) and A beta (1-42) obtained from temporal cortex of MPS patients. Although no neurofibrillary tangles, senile plaques, or tau-positive lesions were detected in any of the MPS brains studied here, antibodies directed against A beta (1-40) intensely and diffusely stained the cytoplasm of cells throughout the brains of the MPS patients and the caprine MPS model. The ELISA assay also demonstrated a significant 3-fold increase in the level of soluble A beta (1-40) in the MPS brains compared with normal control brains. Thus, at least some of the metabolic defects that lead to accumulations of glycosaminoglycans in MPS also are associated with an increase in immunoreactive A beta (1-40) within the cytoplasmic compartment where they could contribute to the dysfunction and death of affected cells in these disorders, but not induce the formation of plaques and tangles. Models of MPS may enable mechanistic studies of the role A beta and glycosaminoglycans play in the amyloidosis that is a neuropathological feature of AD.

Adolescent↗

Glial cytoplasmic inclusions in white matter oligodendrocytes of multiple system atrophy brains contain insoluble alpha-synuclein.

Recently, alpha-synuclein was shown to be a structural component of the filaments in Lewy bodies (LBs) of Parkinson's disease (PD), dementia with LBs (DLB) as well as the LB variant of Alzheimer's disease, and this suggests that alpha-synuclein could play a mechanistic role in the pathogenesis of these disorders. To determine whether alpha-synuclein is a building block of inclusions in other neurodegenerative movement disorders, we examined brains from patients with multiple system atrophy (MSA) and detected alpha-synuclein, but not beta- or gamma-synuclein, in glial cytoplasmic inclusions (GCIs) throughout the MSA brain. In MSA white matter, alpha-synuclein-positive GCIs were restricted to oligodendrocytes, and alpha-synuclein was localized to the filaments in GCIs by immunoelectron microscopy. Finally, we demonstrated that insoluble alpha-synuclein accumulated selectively in MSA white matter with alpha-synuclein-positive GCIs. Taken together with evidence that LBs contain insoluble alpha-synuclein, our data suggest that a reduction in the solubility of alpha-synuclein may induce this protein to form filaments that aggregate into cytoplasmic inclusions, which contribute to the dysfunction or death of glial cells as well as neurons in neurodegenerative disorders with different phenotypes.

Actin Cytoskeleton↗

RNA sequestration to pathological lesions of neurodegenerative diseases.

Cytoplasmic RNA species have been identified recently within neurofibrillary tangles and senile plaques of Alzheimer's disease brain. To determine whether RNA sequestration is a common feature of other lesions found in progressive neurodegenerative disorders, acridine orange histofluorescence was employed, alone or in combination with immunohistochemistry and thioflavine-S staining to identify RNA species in paraffin-embedded brain tissue sections. Postmortem samples came from 39 subjects with the following diagnoses: Alzheimer's disease, amyotrophic lateral sclerosis/parkinsonism-dementia complex of Guam, corticobasal degeneration, diffuse Lewy body disease, normal controls, multiple system atrophy, Parkinson's disease, Pick's disease, progressive supranuclear palsy, and Shy-Drager syndrome. RNAs were detected in neurofibrillary tangles and neuritic senile plaques as well as in Pick bodies. However, Lewy bodies, Hirano bodies, and cytoplasmic glial inclusions did not contain abundant cytoplasmic RNA species. These observations demonstrate the selective localization of RNA species to distinct pathological lesions of neurodegenerative disease brains.

Acridine Orange↗

Morphologic and temporal characterisation of lesions in an enhanced murine model of Serpulina hyodysenteriae infection.

This laboratory has previously reported a murine model of Serpulina hyodysenteriae infection in which mice fed a defined diet, Teklad 85420 (TD), developed caecal lesions more consistently than mice fed a conventional rodent chow (CRC). The objectives of the current studies were to characterise and compare the time of onset of lesions, the morphological nature and severity of lesions and the extent of colonisation by S. hyodysenteriae in mice fed the two diets. In the first of two experiments, 50 C3H/HeJ and 50 C3H/HeOuJ mice were fed either TD or CRC and then half of each group was infected with S. hyodysenteriae. Mice (n = 5) from each group were killed and examined on days, 1, 2, 4, 9 or 17 after infection. Each mouse was examined grossly and microscopically and assigned lesion scores based on lesion severity. The second experiment was designed in an identical way to the first, but had slightly smaller group sizes (n=20). Mice (n=4) were killed for necropsy at the same five time points after infection and their caeca were homogenised and examined by quantitative bacteriology with media selective for S. hyodysenteriae. There were no differences in any finding due to mouse strain. Group lesion scores over the entire experimental period were significantly higher in mice fed TD (mean total lesion index = 13) than in mice fed CRC (mean total lesion index = 8.8). Lesions were also temporally distributed in a significantly different manner in that they appeared earlier (day 1) and persisted longer in the TD-fed mice in comparison to CRC-fed mice. Furthermore, lesions of equivalent severity from each treatment group presented identical microscopic features. Finally, quantitative bacteriological results indicated that there was no significant difference in the number of cfu of S. hyodysenteriae isolated from mice fed TD and those fed CRC. These results demonstrate that the characteristic severe lesions associated with S. hyodysenteriae infection in mice can occur 1 day after oral challenge in mice fed Teklad diet 85420. Bacteriological results further indicate that the enhancement of lesion formation in this model is not due to any significant effect of the diet on numbers of spirochaetes in the caeca of infected mice.

Animals↗