Biomedical subjects

Herbert Budka

Publications and source records attributed to Herbert Budka.

At least 55 records · Page 3Linked to original sources

PubMed2004

Rationale for diagnosing human prion disease.

Human prion diseases (PrD) like Creutzfeldt-Jakob disease (CJD) include sporadic, acquired and familial neurodegenerative disorders. The central events in the neuropathological process of PrDs are severe neuronal loss, spongiform change and accumulation of abnormal prion protein (PrPSc). The latter is a conformational variant of the host-encoded cellular PrP (PrPC), a copper-binding protein. The physiological role of PrPC is debated. Definitive diagnosis of PrD is based on post mortem demonstration of PrPSc by immunohistochemistry or Western blot. Mutations in the PrP gene (PRNP), the polymorphic site at codon 129, and the molecular characteristic of protease resistant PrP influence the phenotype. Clinical symptoms, cranial MRI scan, EEG and investigation of 14-3-3 protein in cerebrospinal fluid (CSF) suggest a diagnosis of probable CJD. Variant CJD, related to bovine spongiform encephalopathy, shows a different clinical course, symmetrical high intensity MRI signal in the pulvinar, presence of PrPSc in tonsil biopsy tissue, and a lower sensitivity of CSF 14-3-3 protein compared to sporadic CJD. Future possibilities in diagnosis of PrDs include either the demonstration of PrPSc in body fluids or disease associated changes in laboratory variables or gene expression.

14-3-3 Proteins↗

PubMed2004

Ki-67 immunolabeling index is an accurate predictor of outcome in patients with intracranial ependymoma.

Histopathologic grading of ependymomas is considered unreliable in terms of outcome prediction. Quantification of tumor cell proliferation may be useful for outcome prediction. We analyzed prognostic and predictive values of tumor cell proliferation rates using anti-Ki-67 antigen (MIB-1 antibody) and anti-topoisomerase-IIalpha (Topo-IIalpha) immunolabeling on tumor samples of 103 consecutive ependymoma patients 0.1 to 74.4 years of age. In this patient cohort, the following clinical and histopathologic parameters showed significant correlation with overall survival on univariate analysis: extent of resection, use of an operating microscope, radiologic imaging with computed tomography and/or magnetic resonance imaging, radiotherapy, tumor size (cutoff 3 cm), WHO grade, presence of tumor necrosis, increased cellularity, microvascular proliferation, and low/high Ki-67 and Topo-IIalpha indices (cutoff 20.5% and 9.4%, respectively). On multivariate analysis, incomplete resection and high Ki-67 index remained independent factors of adverse patient outcome. In Kaplan-Meier survival analysis, low (<20.5%) or high (> or = 20.5%) Ki-67 indices predicted favorable (> or = 5 years) or unfavorable (<5 years) patient outcome at 79% and 70%, respectively. We conclude that Ki-67 immunolabeling index is an independent prognostic factor and accurate predictor of outcome in patients with intracranial ependymoma. Thus, assessment of Ki-67 index in intracranial ependymoma is useful for outcome prediction in the routine diagnostic setting.

Adolescent↗

PubMed2004

Contribution of neuropathology to the understanding of human prion disease.

Neuropathology is an important tool for definitive diagnosis of sporadic, genetic, and acquired prion disease. Classical neuropathological hallmark is the highly disease-specific spongiform change accompanied by neuronal loss, astro- and microgliosis. Spongiform change of the neuropil consists of either microcystic or confluent vacuoles and varies greatly within the same brain. In addition, the most important aspect of confirmatory diagnosis is the demonstration of disease-associated prion protein (PrP(d)) by immunohistochemistry or Western blotting. Different PrP(d) immunostaining patterns include patchy/perivacuolar surrounding spongiform change, diffuse/synaptic, perineuronal, or plaque type. The latter includes unicentric kuru-type plaques or multicentric plaques as in the peculiar genetic prion disorder, Gerstmann-Sträussler-Scheinker disease. PrP(d) immunostaining patterns correlate well with phenotypes defined by the polymorphic codon 129 and the type of protease resistant PrP(d) seen on Western blots. PrP(d) immunoreactivity in the cerebellum may be highly informative about disease subtypes. Although the central nervous system is the major site of PrP(d) accumulation, it may also be observed in peripheral nerves as adaxonal deposits; in skeletal muscle as granular immunoreactivity in particular in abundance in a unique instance of concomitant Creutzfeldt-Jakob disease and inclusion body myositis; as well as associated with dendritic cells and macrophages in vessel walls. A subset of inhibitory GABAergic neurons is selectively affected in experimental and human prion disease. The central pathogenetic cascade includes oxidative stress and apoptosis. Deposition of terminal complement components on neurons accompanies tissue damage.

Blotting, Western↗

PubMed2004

Gerstmann-Sträussler-Scheinker disease. I. Human diseases.

Gerstmann-Sträussler-Scheinker disease (GSS) is a slowly progressive hereditary autosomal dominant disease (OMIM: 137440) and the first human transmissible spongiform encephalopathy (TSE) in which a mutation in a gene encoding for prion protein (PrP) was discovered. Its true prevalence is difficult to estimate but figures within the range of 1-10/100,000,000 are quoted. GSS is defined as a neurodegenerative disease "in family with dominantly inherited progressive ataxia and/or dementia): encephalo(myelo)pathy with multi-centric PrP plaques". In this review, we summarise data on all the families with GSS. The hallmark of the GSS neuropathology is the multi-centric plaque but the pattern varies between families. In the second part of this review the experimental data using experimental models of GSS in transgenic mice are summarised as well as structural biology of mutated PrP in GSS.

Animals↗

PubMed2004

Echigo-1: a panencephalopathic strain of creutzfeldt-jakob disease. I. neuropathological and immunohistochemical studies.

We demonstrate an unusually intensive accumulation of prion protein (PrP) on neuronal membranes in hamsters infected with the Echigo-1 panencephalopathic strain of Creutzfeldt-Jakob disease. This stands in strong contrast with the poor vacuolation in this model. Several distinct patterns of PrP(TSE) deposit were observed in the brain. The first type consisted of a fine granular "synaptic"/diffuse type of accumulation which, especially in the cerebral cortex, appeared laminar. Deposits frequently coalesced to form plaque-like structures. The second pattern consisted of perivascular plaque-like accumulations. When a vessel was cut longitudinally, these formed long linear arrays of plaques and smaller globules. The third, and most striking, consisted of perineuronal deposits. These formed small dots and coarser globules which were densely situated on the neuronal membrane on both cell bodies and their processes.

Animals↗

PubMed2004

Echigo-1: a panencephalopathic strain of Creutzfeldt-Jakob disease. II. Ultrastructural studies in hamsters.

In this and a companion paper we present immunohistochemical and ultrastructural data on hamsters infected with the Echigo-1 strain of Creutzfeldt-Jakob disease. Ultrastructurally, two types of vacuoles were readily discriminated in the brain: the grey matter vacuoles of spongiform change and intramyelin vacuoles. The vacuoles were always membrane-bound; the membranes were single or double. The axons were entirely missing from the plane of the sections or, if visible, were shrunken and attached to the innermost layer of the myelin. It was noteworthy that some vacuoles indented cell bodies or processes and thus were reminiscent of the intraneuronal vacuoles typical for natural scrapie, BSE and CWD in ungulates and cervids but not of the vacuoles encountered in rodent models of scrapie and CJD. We also noticed vacuoles distending myelinated fibres in which the axons had become dystrophic. Some axons underwent Wallerian degeneration while others met the criteria for dystrophic neuritis. Both alterations existed in the same areas. Typical dystrophic neurites contained abnormal subcellular organelles, mainly electron-dense lysosomal inclusions. Other neurites contained numerous multi-vesicular bodies and autophagic vacuoles. Nuclear paracrystalline rod-like inclusions were occasionally visible in neurons while other inclusions comprised spiroplasma-like inclusions in synaptic boutons. The robust cellular reactions consisted of reactive astrocytes and macrophages filled with cellular debris. It is of note that complex autophagic vacuoles were observed in the cytoplasm of neurons.

Animals↗

PubMed2003

Increased 14-3-3 immunoreactivity in glial elements in patients with multiple sclerosis.

14-3-3 proteins have been shown to be increased in the cerebrospinal fluid from patients with several kinds of neurological diseases, including multiple sclerosis (MS). To investigate whether 14-3-3 proteins are closely related to the pathogenesis of MS, we performed immunohistochemical studies for 14-3-3 in autopsied brains from ten patients with MS, five patients with progressive multifocal leukoencephalopathy (PML), and seven normal control subjects. Formalin-fixed, paraffin-embedded sections from all cases were immunostained with a specific anti-14-3-3 antibody, and some sections from the MS cases were double-immunostained with antibodies raised against 14-3-3 and glial markers. In the normal control brains, 14-3-3 immunoreactivity was localized mainly in the neuronal somata and processes, and some glial cells showed only weak immunoreactivity. In the plaque lesions from the MS cases, the astrocytes and oligodendrocytes were intensely immunostained, and strong immunoreactivity was also found in some microglia and macrophages, most of which were located in the perivascular areas. In the PML brains, a similar immunolabeling pattern was observed in the demyelinated lesions, in which the astrocytes and oligodendrocytes exhibited dense 14-3-3 immunoreactivity. Our results suggest that 14-3-3 may be up-regulated in the glial cells, especially in astrocytes and oligodendrocytes, in patients with MS or PML. The exaggerated 14-3-3 accumulation in these glial elements may be associated with the pathogenesis of both demyelinating disorders.

14-3-3 Proteins↗

PubMed2003

Rosette-forming glioneuronal tumor of the fourth ventricle.

Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle has been reported recently as a novel type of primary CNS neoplasm. We present the case of a 35-year-old male patient with RGNT of the fourth ventricle. The tumor was found incidentally; the patient did not suffer from any neurological symptoms. The tumor mass involved the caudal cerebellar vermis, filled the fourth ventricle and protruded into the caudal part of the mesencephalic aquaeduct. Smaller tumor nodules were visible in the adjacent right cerebellar hemisphere. Histologically, prominent neurocytic rosettes with synaptophysin expression were embedded in a glial tumor component resembling pilocytic astrocytoma. Clinicopathological features of our case closely resemble those reported in the original description. Thus, our case confirms RGNT as a new distinct type of primary CNS neoplasm. Due to its distinct features, adoption of RGNT as a new entity into the WHO classification of tumors should be considered.

Adult↗

PubMed2003

Distinct time pattern of complement activation and cytotoxic T cell response in Guillain-Barré syndrome.

Humoural and cellular immune mechanisms are involved in the pathogenesis of Guillain-Barré syndrome (GBS). While activation of complement has been implicated in the initiation of myelin damage, we provide data here on the role of cellular cytotoxicity in GBS. Archival autopsy tissues including spinal roots, dorsal root ganglia and peripheral nerve were examined from 11 subjects who died 1 day to 8 weeks after onset of symptoms from GBS exhibiting a primary demyelinating pathology. In order to study the extent of humoural and cellular immune processes with regard to disease duration, a broad panel of antibodies to immunological and cellular markers was used to visualize the stage of demyelination, the deposition of complement components and expression of CD59, and to characterize cell infiltrates. Deposits of C9neo antigen on degenerating myelin sheaths were predominantly detected in acute cases. Expression of CD59 was upregulated on demyelinating fibres, but did not correlate with the presence of C9neo antigen or duration of disease. Quantitative analysis of endoneurial T cells showed a correlation between the density of CD3+ T cells per square unit and the degree of demyelination, but not with the duration of disease. The ratio of CD8+ to CD3+ T cells, however, was significantly increased in cases of GBS with a subacute course. Granzyme B positive lymphocytes and upregulation of MHC class I molecules on Schwann cells and myelin sheaths were detected in cases with more than 4 weeks disease duration. These findings implicate an important role of cytotoxic T cell responses for myelin damage in subacute stages of GBS.

Adult↗

PubMed2003

D18G transthyretin is monomeric, aggregation prone, and not detectable in plasma and cerebrospinal fluid: a prescription for central nervous system amyloidosis?

Over 70 transthyretin (TTR) mutations facilitate amyloidosis in tissues other than the central nervous system (CNS). In contrast, the D18G TTR mutation in individuals of Hungarian descent leads to CNS amyloidosis. D18G forms inclusion bodies in Escherichia coli, unlike the other disease-associated TTR variants overexpressed to date. Denaturation and reconstitution of D18G from inclusion bodies afford a folded monomer that is destabilized by 3.1 kcal/mol relative to an engineered monomeric version of WT TTR. Since TTR tetramer dissociation is typically rate limiting for amyloid formation, the monomeric nature of D18G renders its amyloid formation rate 1000-fold faster than WT. It is perplexing that D18G does not lead to severe early onset systemic amyloidosis, given that it is the most destabilized TTR variant characterized to date, more so than variants exhibiting onset in the second decade. Instead, CNS impairment is observed in the fifth decade as the sole pathological manifestation; however, benign systemic deposition is also observed. Analysis of heterozygote D18G patient's serum and cerebrospinal fluid (CSF) detects only WT TTR, indicating that D18G is either rapidly degraded postsecretion or degraded within the cell prior to secretion, consistent with its inability to form hybrid tetramers with WT TTR. The nondetectable levels of D18G TTR in human plasma explain the absence of an early onset systemic disease. CNS disease may result owing to the sensitivity of the CNS to lower levels of D18G aggregate. Alternatively, or in addition, we speculate that a fraction of D18G made by the choroid plexus can be transiently tetramerized by the locally high thyroxine (T(4)) concentration, chaperoning it out into the CSF where it undergoes dissociation and amyloidogenesis due to the low T(4) CSF concentration. Selected small molecule tetramer stabilizers can transform D18G from a monomeric aggregation-prone state to a nonamyloidogenic tetramer, which may prove to be a useful therapeutic strategy against TTR-associated CNS amyloidosis.

Amino Acid Sequence↗

PubMed2003

Distinctive cerebellar immunoreactivity for the prion protein in familial (E200K) Creutzfeldt-Jakob disease.

We have compared the immunomorphological spectrum of the deposition of the disease-associated prion protein (PrP(Sc)) in the cerebral and cerebellar cortex of 32 Creutzfeldt-Jakob disease (CJD) patients with the PrP gene (PRNP) E200K mutation to 45 sporadic CJD and 14 other genetic prion disease cases. PrP deposits correlate with the genotype at the methionine/valine (MV) polymorphic codon 129. While the diffuse/synaptic and patchy/perivacuolar PrP deposits and PrP plaques have a similar distribution and correlation with the genotype at codon 129 as in sporadic CJD, an additional peculiar PrP immunostaining pattern occurs in the cerebellum in 81% E200K mutation brains including 93% of M129M, 71% of M129V, but not in the single V129V case. It is localized to the molecular layer and consists of coarse granular PrP deposits arranged in a stripe-like manner predominantly perpendicular to the surface, closely resembling the parasagittal arborization of climbing fibers. Our results suggest that (1) the type of PrP deposits in the cerebellum may suggest genetic disease and the need for genetic testing; and (2) the peculiar stripes of PrP deposits might reflect selective vulnerability of cerebellar structures.

Cerebellum↗

PubMed2003

Nucleus-specific alteration of raphe neurons in human neurodegenerative disorders.

Neurodegenerative diseases share symptoms suggested to be related to the serotonergic system. To evaluate the involvement of serotonergic raphe nuclei, we compared the percentage of neurons synthesizing serotonin in the nucleus centralis superior (NCS), raphe obscurus and pallidus (NROP) in Alzheimer's disease (AD), progressive supranuclear palsy (PSP), Parkinson's disease (PD), multiple system atrophy (MSA), and control brains. We used immunohistochemistry for tryptophan hydroxylase (TpOH), phosphorylated tau, and alpha-synuclein. We observed a significant decrease in the NCS in the NROP in AD, but a significant increase in PSP and MSA. Cytoskeletal pathology was present in the NCS and NROP to a variable degree. We conclude that there is disease- and nucleus-specific alteration of serotonin synthesis in the raphe.

Aged↗

PubMed2003

Neuropathology of prion diseases.

In prion diseases, neuropathology has remained the most important tool to give a definite diagnosis, and neuropathological research has contributed significantly to our current pathogenetic understanding. Immunohistochemistry for the disease-associated prion protein (PrP(Sc)) is indispensable for the neuropathological confirmation of prion diseases. The amount and distribution of PrP(Sc) deposits do not always correlate with type and severity of local tissue damage. PrP(Sc) deposition occurs only where neuronal parenchyma is present; in scarred infarctions with prominent gliosis, PrP(Sc) does not accumulate. Early, severe and selective loss affects a subset of inhibitory GABAergic neurons both in human and experimental prion diseases. The central pathogenetic cascade includes oxidative stress to neurons and their apoptosis. New patterns of PrP(Sc) immunoreactivity include granular ganglionic and tiny adaxonal PrP(Sc) deposits in peripheral nervous tissue, and dendritic cells and macrophages in vessel walls, suggesting that mobile haematogenous cells may be involved in spread of prions.

Animals↗

PubMed2003

Molecular classification of sporadic Creutzfeldt-Jakob disease.

According to the protein-only hypothesis of prion propagation, an abnormal isoform (designated PrP(Sc)) of the cellular prion protein (PrP(C)) is the principal or sole component of transmissible prions. However, the existence of multiple prion strains has been difficult to accommodate within this hypothesis. We have previously reported the identification of four types of human PrP(Sc) associated with sporadic and acquired human prion diseases. These PrP(Sc) types are distinguished by differing molecular mass of fragments following limited proteinase K digestion and by differing ratios of di-, mono- and unglycosylated PrP(Sc). That these discrete biochemical features of PrP(Sc) are serially transmissible to human PrP in transgenic mice following experimental transmission suggests that they may be responsible for encoding prion strain diversity. Here we present detailed clinical, pathological and molecular data from a large number of sporadic Creutzfeldt-Jakob disease (CJD) cases. We show that PrP(Sc) types are associated with codon 129 status, duration of illness and neuropathological phenotype. A novel PrP(Sc) type is presented, illustrating further heterogeneity in CJD, and suggesting that further molecular subtypes of CJD may exist at lower frequencies. A molecular classification of sporadic CJD is proposed.

Adult↗

PubMed2003

Fluorescent in situ hybridization on isolated tumor cell nuclei: a sensitive method for 1p and 19q deletion analysis in paraffin-embedded oligodendroglial tumor specimens.

In oligodendroglial neoplasms, losses of chromosomal material at 1p and 19q associate with chemosensitivity and prolonged survival. Thus, 1p/19q testing is increasingly proposed for use in brain tumor diagnosis and prognostic assessment. Fluorescent in situ hybridization (FISH) is a classic technique for investigation of 1p/19q status in paraffin-embedded tissues. A major limitation of this method is truncation of tumor cell nuclei complicating assessment of hybridization results. In our study, we analyzed 1p and 19q status in a series of 79 oligodendroglial neoplasms (49 oligodendrogliomas, 30 oligoastrocytomas, WHO: 57 Grade II, 22 Grade III tumors) and controls (gliotic brain tissue: n = 4, diffuse low-grade astrocytoma: n = 4) using FISH on isolated whole tumor cell nuclei, prepared as cytospin preparations, thus bypassing the problem of nuclear truncation. For interpretation of FISH results, we used consensus criteria as defined by the SIOP-Europe Neuroblastoma Study Group for analysis of peripheral neuroblastic tumors. FISH yielded interpretable results in 98.7% for 1p and 92.1% for 19q. Chromosome 1p/19q alterations comprised deletions (1p: 79.5%, 19q: 80%) and imbalances (1p: 11.5%, 19q: 12.9%). 1p aberrations were more frequent in oligodendroglioma than in oligoastrocytoma (100% versus 75.9%, P =.001). The frequency of 1p/19q alterations was not significantly different in WHO Grade II or Grade III tumors or in primary and recurrent tumors. We conclude that FISH on isolated cell nuclei, with application of the SIOP Europe Neuroblastoma consensus criteria, is a sensitive method for detection and interpretation of 1p and 19q aberrations in paraffin-embedded tissue specimens of oligodendroglial neoplasms.

Brain Neoplasms↗

PubMed2003

Vascular patterns in glioblastoma influence clinical outcome and associate with variable expression of angiogenic proteins: evidence for distinct angiogenic subtypes.

No data exist on angiogenic patterns and their prognostic impact in human glioblastoma. Such data are relevant for translation of antiangiogenic therapies into clinical applications. Using immunohistochemistry for CD34, we assessed vascular patterns in 114 primary glioblastomas. Vascular patterns comprised unevenly distributed glomeruloid/garland-like/clustered bizarre vascular formations and evenly distributed delicate capillary-like microvessels ("classic" vascular pattern). The combination of low content of bizarre vascular formations and prominent classic vascular pattern (n=29) was an independent factor for longer survival (p=0.006, Cox regression), as well as postoperative high Karnofsky performance status (p=0.005). In patients with a prominent classic vascular pattern, there was no difference of MIB1 labeling index whereas microvessel density and apoptotic index (TUNEL) were significantly higher as compared to all other patients (p<0.05). In addition, diffuse expression of hypoxia-inducible factor (HIF)-1alpha and strong expression of vascular endothelial growth factor were more common (p<0.05, Chi-square test). FISH revealed loss of chromosomes 1p and 19q only in 1/7 long-time survivors with classic pattern. We conclude that vascular patterns in primary glioblastoma influence clinical outcome and associate with variable expression of angiogenic proteins. Our findings denote for the first time distinct angiogenic subtypes of human glioblastoma which may prove relevant for anti-angiogenic therapy approaches.

Adult↗

PubMed2002

Severe depletion of mitochondrial DNA in spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a neuromuscular disorder in childhood leading to a dramatic loss of muscle strength. Functional investigations with high-resolution polarography and enzyme measurements of the respiratory chain revealed lowered activities in muscle tissue of SMA patients. To gain a better understanding of this low energy supply we analyzed the amount of mitochondrial DNA (mtDNA) in skeletal muscle of 20 unrelated children with genetically proven SMA and 31 controls. Quantitative Southern blot analysis revealed a severe and homogeneous decrease in the content of muscle mtDNA in relation to nuclear DNA in SMA patients (90.3+/-7.8%), whereas by immunofluorescence no decrease in the number of mitochondria was detected. In addition, a two- to threefold reduction of the nuclear-encoded complex II (succinate dehydrogenase) activity was detected in SMA muscle tissue. Western blot analysis showed a significant reduction of both mitochondrial- and nuclear-encoded cytochrome c oxidase subunits. Our results indicate that mtDNA depletion in SMA is a consequence of severe atrophy, and has to be differentiated by measurement of complex II from an isolated reduction of mtDNA as found in patients with mitochondriocytopathies and the so-called mtDNA depletion syndrome.

Adolescent↗

PubMed2002

The prion protein in human neurodegenerative disorders.

We evaluate cellular prion protein (PrP(C)) immunoreactivity (IR) in Alzheimer's, Parkinson's, diffuse Lewy body, and motor neuron diseases (MND), progressive supranuclear palsy, and multiple system atrophy. We use immunohistochemistry for PrP, including five monoclonal antibodies against different epitopes and three different pretreatments, alpha-synuclein, phosphorylated tau, beta-amyloid, and ubiquitin. Disease-specific inclusions are devoid of PrP(C) IR. Using double immunofluorescence and confocal laser microscopy we observe focal overlapping of PrP(C) with tau and with alpha-synuclein in early, but not in fully developed inclusions. However, PrP(C) IR neurons may contain abnormal tau or alpha-synuclein aggregates. Additionally, we observe a loss of PrP(C) IR in anterior horn neurons in MND. Our results suggest that expression of PrP(C) reflects a general response to cellular stress rather than specific co-operation in aggregation of other proteins.

Amyloid beta-Peptides↗