Showing papers by "Herbert Budka published in 2002"

Mutations of the prion protein gene phenotypic spectrum

Abstract: Prion diseases are inherited in 5–15 % of cases. They are classified according to changes in the prion protein gene (PRNP) or conventionally according to phenotype as Gerstmann-Straussler-Scheinker disease (GSS), fatal familial insomnia (FFI), or familial Creutzfeldt-Jakob disease (fCJD). Point mutations and insertions within PRNP form the genetic background. We report the results of a systematic analysis of over 500 case reports of patients with PRNP abnormalities. We compare clinical, neuropathological and molecular data in five groups, namely GSS, FFI, fCJD, base pair insertion (BPI), and all cases collectively. Clinical presentation overlaps between mutations, but some have characteristic features (e. g. P105L, D178N–129M, T183A). Some mutations, especially in the lack of sufficient family history, in earlier phases tend to resemble other neurodegenerative disorders like multiple system atrophy, corticobasal degeneration or familial diseases such as late-onset spinocerebellar ataxia, spastic paraparesis, frontotemporal dementia, or Alzheimer's disease. The codon 129 polymorphism has a phenotypic influence in inherited prion diseases, as in non-genetic forms, but additional factors might be considered as background for phenotypic variability.

14-3-3 proteins in Lewy bodies in Parkinson disease and diffuse Lewy body disease brains.

Abstract: Several components of Lewy bodies have been identified, but the precise mechanism responsible for the formation of Lewy bodies remains undetermined. The 14-3-3 protein family is involved in numerous signal transduction pathways and interacts with alpha-synuclein, which is a major constituent of Lewy bodies. To elucidate the role of 14-3-3 proteins in neuro-degenerative disorders associated with Lewy bodies, we performed immunohistochemical studies on 14-3-3 in brains from 5 elderly control subjects and from 10 patients with Parkinson disease (PD) or diffuse Lewy body disease (DLBD). In the normal controls, 14-3-3-like immunoreactivity was mainly observed in the neuronal somata and processes in various cortical and subcortical regions. In the PD and DLBD cases, a similar immunostaining pattern was found and immunoreactivity was generally spared in the surviving neurons from the severely affected regions. In addition, both classical and cortical Lewy bodies were intensely immunolabeled and some dystrophic neurites were also immunoreactive for 14-3-3. Our results suggest that 14-3-3 proteins may be associated with Lewy body formation and may play an important role in the pathogenesis of PD and DLBD.

A comparative study on the expression of cyclooxygenase and 5-lipoxygenase during cerebral ischemia in humans.

Abstract: Prostaglandins and leukotrienes (eicosanoids), metabolites of the arachidonic acid pathway, are subjected to altered synthesis or relocation after an ischemic insult. Although cyclooxygenase (COX) expression has been reported in human cerebral ischemia, no information is available on the expression of 5-lipoxygenase (5-LO) and its topographical correlation to COX induction. The objective of this study was to elucidate the comparative distribution of eicosanoids in ischemic tissues. COX and 5- LO, key enzymes for the synthesis of prostaglandins and leukotrienes, respectively, were examined in autopsied brains. COX1 was expressed intensely in the microglia but weakly in the neurons in control brains. These COX1-immunoreactive microglia showed a more activated form following ischemic damage and hypoxemia. In contrast, COX2 was absent in the control brains, and was induced robustly in the neuronal cell bodies and dendrites during the acute stages of focal ischemic damage, and then subsided at the subacute stages. These COX2-immunoreactive neurons accumulated in the peri-infarct regions, but were absent from the distant regions. In focal ischemic damage and Binswanger's disease, COX2 was up-regulated in the microglia. Neuronal immunostaining for 5-LO was up-regulated occasionally during hypoxemia and focal ischemic damage. Glial cells immunoreactive for 5-LO appeared in the foci of the ischemic damage, with small blood vessels being infiltrated by 5-LO-immunoreactive mononuclear leukocytes. These findings indicate that the isozymes of COX are differentially regulated depending on the cellular source and the types of ischemic damage, and that vascular 5-LO may accelerate the migration of leukocytes and augment the blood-brain barrier permeability. The possibility of increased substrate availability for the other should be noticed in specific inhibition of either COX or 5-LO since these two enzymes are accumulated in parallel in ischemic tissues.

Accumulation of 14-3-3 proteins in glial cytoplasmic inclusions in multiple system atrophy.

Abstract: Glial cytoplasmic inclusions are the pathological hallmark of multiple system atrophy. However, the molecular mechanisms underlying the formation of glial cytoplasmic inclusions remain unclear. Alpha-synuclein, a major component of glial cytoplasmic inclusions, has the ability to interact with 14-3-3 proteins, which mediate several types of signal transduction pathways. To elucidate the role of these 14-3-3 proteins in patients with multiple system atrophy, we performed immunohistochemical studies on 14-3-3 in brain tissue specimens from 7 control subjects and from 15 patients with multiple system atrophy. In both control and multiple system atrophy cases, 14-3-3 immunoreactivity was observed mainly in the neuronal somata and proximal processes, as well as the nerve fibers. Even in the severely affected regions of patients with multiple system atrophy, 14-3-3 immunoreactivity generally was spared in the surviving neurons, some of which were strongly immunolabeled. In addition, numerous glial cytoplasmic inclusions were intensely immunostained, and neuronal cytoplasmic inclusions and dystrophic neurites were also immunoreactive for 14-3-3. Our results suggest that an aberrant accumulation of 14-3-3 proteins may occur in brains affected by multiple system atrophy, and that 14-3-3 proteins may be associated with the pathogenesis of multiple system atrophy.

Disease-associated prion protein in vessel walls.

Abstract: Human prion diseases like Creutzfeldt-Jakob disease are infectious, inherited, or sporadic neurodegenerative disorders, characterized by the accumulationof an abnormal isoform of the host-encoded prion protein. This affects nervous tissue in sporadic Creutzfeldt-Jakob disease and, additionally, in lymphoid tissue in bovine spongiform encephalopathy-linked variant Creutzfeldt-Jakob disease. Experimental studies have established the involvement of cells of the lymphoid and peripheral nervous system in the transport of prions to their target central nervous system tissue. To evaluate the role of vessel wall-associated mobile cells, we obtained formalin-fixed tissue blocks from various brain regions and/or basal arteries from sporadic, variant and iatrogenic Creutzfeldt-Jakob disease, and unselected control cases. We demonstrate disease-associated prion protein deposits in intracranial vessel walls, in sporadic and variant Creutzfeldt-Jakob disease by performing immunohistochemical staining and paraffin-embedded tissue blotting. Using double immunofluorescence, these deposits co-localize with HLA-DR and S-100 immunoreactive cells in the intima, which are components of the vascular-associated dendritic cell network, as well as with HLA-DR and CD-68 immunopositive macrophages of the intima and media. We conclude that mobile cells in vessel walls like dendritic and monocyte/macrophage lineage cells may be involved in spread of disease-associated prion protein and possibly also of infectivity.

Prognostic relevance of p53 protein expression in glioblastoma.

Abstract: TP53 plays a key role in cellular response to DNA-damaging agents, and mutation of this gene, which is associated with immunohistochemically detectable p53 protein accumulation, may influence response to chemo- and radiotherapy. We investigated immunohistochemically the influence of p53 protein accumulation in 114 consecutive cases of primary glioblastoma treated by surgery and adjuvant radio- and chemotherapy. In addition, we determined cellular proliferation index using the antibody MIB-1 and apoptotic index of tumor cells using the TUNEL-assay. Twenty-nine patients (25.4%) were considered as positive with regard to p53 protein expression (>50% p53 immunostained tumor cells). Patients with p53 positive glioblastomas were significantly younger (mean age 54.4+/-2 years) than those with p53 negative tumors (mean age 61.4+/-1.1 years) (p=0.002, Mann-Whitney test). While no significant difference in apoptotic index was found, we observed a significantly higher MIB-1 labeling index (LI) in patients with p53 positive tumors (median LI: 36.4%) compared to p53 negative ones (median LI: 23.8%) (p=0.005, Mann-Whitney test). p53 protein expression was associated with significantly longer survival in univariate analysis (p=0.0399, log-rank test). In multivariate analysis of overall survival (Cox regression) only postoperative Karnofsky performance status remained as independent prognostic factor. We conclude that glioblastoma patients with immunohistochemically detectable p53 protein expression, who received adjuvant radio- and chemotherapy, have a significantly better overall survival, possibly due to increased sensitivity to this adjuvant treatment.

Spontaneous mutations in the prion protein gene causing transmissible spongiform encephalopathy.

Abstract: We analyzed the prion protein gene (PRNP) region in patients with transmissible spongiform encephalopathy associated with the PRNP D178N mutation. The results suggest that the D178N chromosomes had independent origins in each affected pedigree or apparently sporadic case. A de novo spontaneous PRNP mutation was observed. We provide evidence that hereditary and apparently sporadic transmissible spongiform encephalopathy cases associated with the D178N mutation result from multiple recurrent mutational events.

Fibrous meningeal tumours with extensive non-calcifying collagenous whorls and glial fibrillary acidic protein expression: the whorling-sclerosing variant of meningioma.

Abstract: Meningiomas comprise a wide range of morphological patterns. We describe unusual fibrous meningeal tumours in two patients, composed of extensive non-calcifying collagenous whorls of varying size, resembling non-calcified psammoma bodies, while interposed tumour cells are sparse. Immunohistochemistry showed expression of S-100, vimentin and glial fibrillary acidic protein, whereas only single tumour cells stained for epithelial membrane antigen. Electron microscopy detected desmosomes or desmosome-like structures in both specimens. We conclude that these tumours represent a peculiar whorling-sclerosing variant of fibrous meningioma. Recognition of this meningioma variant is important in the differential diagnosis of meningioma versus other fibrous tumours of the meninges, including solitary fibrous tumours of the meninges, unusual forms of desmoplastic gliomas or chondroid tumours.

Distribution of intraneuronal immunoreactivity for the prion protein in human prion diseases.

Abstract: Intraneuronal prion protein (PrP) immunoreactivity (INIR), which might represent the non-pathological, cellular form of PrP, needs to be distinguished from disease-associated deposits specific for prion disease (PrD). In adjacent sections of PrD and control brains we applied pretreatments, one of which enhances the immunoreactivity of disease-associated PrP, and another that enhances INIR. We observed an inverse correlation between the proportion of neurons with INIR and the intensity of disease-associated PrP immunoreactivity and severity of lesions. Additionally, we found large intracytoplasmic inclusion-like bodies in ballooned neurons in PrD cases. We noted that the 3F4 (epitope: amino acids 109–112) anti-PrP antibody labels more INIR than antibodies directed against amino acids 23–85 (BG4) or 140–180 (KG9) in PrD cases, in contrast to controls, but all antibodies immunolabel more INIR in PrD brains. The up-regulation of PrP might represent an early loss of function of the non-pathological form of PrP, in parallel with a neurotoxic effect of accumulating disease-associated isoform, as part of the pathogenesis of prion diseases.

Proliferative activity as measured by MIB-1 labeling index and long-term outcome of cerebellar juvenile pilocytic astrocytomas.

Abstract: Proliferative activity of cerebellar juvenile pilocytic astrocytomas (CJPA) and its significance for prognosis was retrospectively investigated. Forty-four consecutive children operated between 1981 and 1997 with a mean age of 8.3 years (3 months to 20 years) were reviewed. Clinical and radiological follow-up was available for 38 patients ranging from 0 to 18 yrs (mean 6.3 years). Proliferative activity was determined by MIB-1 immunohistochemistry on sections of resected tumor specimen. Total resection was achieved in 35 children (79.5%), subtotal in 9 (20.5%). Currently, 31 are tumor-free, 6 have stable remnants, one developed spinal seeding and one died. Radiology revealed a cystic mural node type tumor in 27 patients (61.4%), a solid lesion with a small cyst in 5 patients (11.4%), and a solid tumor in 12 patients (27.3%). Mean MIB-1 labeling index (LI) of all tumors was 4.4% (range 0.6–12%, SD = 2.7) and did not correlate with age, gender, localization, amount of resection, follow-up status, histological appearence or grade of neovascularization, but showed a significant correlation to radiological types: 6.9% in solid tumors versus 3.7% in the cystic mural node type (p = 0.0037). Five year progression-free survival (PFS) of all patients was 84.4%, differences between subgroups of MIB-1 5% (13 patients, PFS = 76.3%) were not significant. CJPA showed a remarkable high MIB-1 LI, but no significant correlation to PFS in this series. Nevertheless, radiologically solid tumors demonstrated a significantly higher MIB-1 LI and thus may need further investigation for possible increased ability of regrowth.

BSE and variant Creutzfeldt-Jakob disease: never say never.

Abstract: (vCJD) rises, the important question on how and to what extent the bovine spongiform encephalopathy (BSE) agent entered the human population has remained unanswered. In face of this scientific and public health issue, Dr. George A. Venters most recently stepped backward to argue in favour of the alternative hypothesis that vCJD is not derived from BSE and is not a new entity [13]. He compared the complex vCJD situation with other foodborne epidemics by conventional infections, but seemed unaware of, or misinformed on, many details concerning transmissible spongiform encephalopathies (TSEs) in general and, specifically, vCJD and BSE. While it is essential in science to keep an open mind, critical assessment is equally required, especially when erratic assertions might endanger necessary precautions for public health. Since Venters’ article has been increasingly quoted by the media and even decision makers, we feel that its flawed argumentation must not go unreplied. Dr. Venters is right that there is no direct evidence that the ingestion of BSE prions induces disease in humans, and that the species barrier between humans and ruminants is likely to be robust [13]. However, he neglects the fact that BSE prions cause disease in felines and non-human primates, species that carry a prion protein (PrP) with several amino acid differences from bovine PrP. Breaking the species barrier is a complex event that does not only involve the similarity between PrP of the host species and that of the donor species, as argued by Dr Venters, but includes other host genetic factors [8], the strain of prion, the amount of infectivity and the route of infection. The correct statement that „people do not get scrapie“ cannot be taken as argument to conclude that BSE is not pathogenic for humans: BSE prions are different from all prions isolated in scrapie-affected sheep. Dr. Venters incorrectly asserted that „the BSE prion does not cause disease in mice carrying the human PrP gene“ [13]. BSE transmits to such mice, though with prolonged incubation periods [6] compared to transgenic mice carrying the bovine PrP gene [12]. This simply supports the notion that cattle are more susceptible to BSE than humans. In addition, biochemical investigations [4] and transmission experiments to macaques [9] demonstrated the similarity of BSE and vCJD, and strain-typing experiments with inbred mice confirmed that the infectious agents of BSE and vCJD are indistinguishable [2]. Dr. Venters also questioned the novelty of vCJD and suggested that a better explanation for its „appearance“ is increased ascertainment of human TSEs in the United Kingdom during the last years [13]. Indeed, improved surveillance has always resulted in an increase of diagnosed cases, in the United Kingdom as well as in other countries. Dr. Venters ignored, however, that a European collaborative study of CJD was established in 1993 (EUROCJD) among several EU and non-EU countries, and extended to all EU member states in 1996 (NEUROCJD) with the major aim to document the incidence of vCJD in Europe [14]. CJD surveillance in Europe is based upon common Herbert Budka · Dominique Dormont · Hans Kretzschmar · Maurizio Pocchiari · Cornelia van Duijn

Myofibrillar (desmin-related) myopathy: clinico-pathological spectrum in 3 cases and review of the literature.

Abstract: Myofibrillar or desmin-related myopathies encompass neuromuscular disorders with abnormal deposits of desmin and myofibrillar alterations. We report 3 unrelated patients presenting with proximal and distal myopathy, and, as a unique congenital syndrome, diffusely distributed myopathy, osteoporosis and myopia. Muscle biopsies shared cytoplasmic inclusions, rimmed vacuoles, and ragged-red-like fibers. Sarcoplasmic inclusions, either plaque-like or amorphous, strongly immunoreacted on dystrophin and variably for desmin, alphaB crystallin and ubiquitin. Cyclin-dependent kinases CDK1, CDK2 and CDK5 were overexpressed in affected fibers. Ultrastructurally, focal myofibrillar disruption was accompanied by tubulo-filamentous inclusions in one case and abundant glycogen and enlarged mitochondria displaying respiratory chain dysfunction at biochemistry in another case. Molecular analysis of the alphaB crystallin gene coding sequence and exons 4, 5 and 6 of the desmin gene did not reveal any mutation. The morphologic denominator of hyaline structures and areas of myofibrillar destruction occurs in heterogeneous conditions and may overlap with features of inclusion body myopathy and mitochondrial myopathy.

Expression of DNA topoisomerase IIalpha in oligodendroglioma.

Abstract: Background: DNA Topoisomerase lla (Topo IIα) is a nuclear enzyme whose expression levels are related to tumor cell growth and to resistance to anticancer chemotherapy. Materials and Methods: Topo IIα expression was assessed immunohisto-chemically in 60 surgical specimens of 47 consecutive oligodendroglioma patients. Expression levels were correlated with the MIB-1 proliferation index and with patient outcome. Results: Topo IIα expression ranges from 0.3 to 40. 1 % and is significantly associated with MIB-1 staining. There is a weak trend to a higher expression of Topo IIα in anaplastic oligodendrogliomas (p = 0.08). Topo lla expression is not related to patient outcome. Conclusion: Topo IIα expression appears to serve as a marker for tumor growth in human oligodendrogliomas. The widely varying expression levels of Topo lla in oligodendroglioma suggest this enzyme could be used for targeted selection of patients for Topo IIα-interfering chemotherapy.