Perry Disease: Expanding the Genetic Basis

Background

Perry disease (or Perry syndrome [PS]) is a hereditary neurodegenerative disorder inevitably leading to death within few years from onset. All previous cases with pathological confirmation were caused by mutations within the cytoskeleton-associated protein glycine-rich (CAP-Gly) domain of the DCTN1 gene.

Objectives

This paper presents the first clinicopathological report of PS due to a novel DCTN1 mutation outside the CAP-Gly domain.

Methods

Clinical and pathological features of the new variant carrier are compared with another recently deceased PS case with a well-known pathogenic DCTN1 mutation and other reported cases.

Results and Conclusions

We report a novel DCTN1 mutation outside the CAP-Gly domain that we demonstrated to be pathogenic based on clinical and autopsy findings.

Phylogeny of Shrew- and Mole-Borne Hantaviruses in Poland and Ukraine

Earlier, we demonstrated the co-circulation of genetically distinct non-rodent-borne hantaviruses, including Boginia virus (BOGV) in the Eurasian water shrew (Neomys fodiens), Seewis virus (SWSV) in the Eurasian common shrew (Sorex araneus) and Nova virus (NVAV) in the European mole (Talpa europaea), in central Poland. To further investigate the phylogeny of hantaviruses harbored by soricid and talpid reservoir hosts, we analyzed RNAlater®-preserved lung tissues from 320 shrews and 26 moles, both captured during 1990-2017 across Poland, and 10 European moles from Ukraine for hantavirus RNA through RT-PCR and DNA sequencing. SWSV and Altai virus (ALTV) were detected in Sorex araneus and Sorex minutus in Boginia and the Białowieża Forest, respectively, and NVAV was detected in Talpa europaea in Huta Dłutowska, Poland, and in Lviv, Ukraine. Phylogenetic analyses using maximum-likelihood and Bayesian methods showed geography-specific lineages of SWSV in Poland and elsewhere in Eurasia and of NVAV in Poland and Ukraine. The ATLV strain in Sorex minutus from the Białowieża Forest on the Polish-Belarusian border was distantly related to the ATLV strain previously reported in Sorex minutus from Chmiel in southeastern Poland. Overall, the gene phylogenies found support long-standing host-specific adaptation.

The Underlying Pathogenesis of Neurovascular Compression Syndromes: A Systematic Review

Neurovascular compression syndromes (NVC) are challenging disorders resulting from the compression of cranial nerves at the root entry/exit zone. Clinically, we can distinguish the following NVC conditions: trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia. Also, rare cases of geniculate neuralgia and superior laryngeal neuralgia are reported. Other syndromes, e.g., disabling positional vertigo, arterial hypertension in the course of NVC at the CN IX-X REZ and torticollis, have insufficient clinical evidence for microvascular decompression. The exact pathomechanism leading to characteristic NVC-related symptoms remains unclear. Proposed etiologies have limited explanatory scope. Therefore, we have examined the underlying pathomechanisms stated in the medical literature. To achieve our goal, we systematically reviewed original English language papers available in Pubmed and Web of Science databases before 2 October 2021. We obtained 1694 papers after eliminating duplicates. Only 357 original papers potentially pertaining to the pathogenesis of NVC were enrolled in full-text assessment for eligibility. Of these, 63 were included in the final analysis. The systematic review suggests that the anatomical and/or hemodynamical changes described are insufficient to account for NVC-related symptoms by themselves. They must coexist with additional changes such as factors associated with the affected nerve (e.g., demyelination, REZ modeling, vasculature pathology), nucleus hyperexcitability, white and/or gray matter changes in the brain, or disturbances in ion channels. Moreover, the effects of inflammatory background, altered proteome, and biochemical parameters on symptomatic NVC cannot be ignored. Further studies are needed to gain better insight into NVC pathophysiology.

Plasma total prion protein as a potential biomarker for neurodegenerative dementia: diagnostic accuracy in the spectrum of prion diseases

AIMS

In the search for blood-based biomarkers of neurodegenerative diseases, we characterized the concentration of total prion protein (t-PrP) in the plasma of neurodegenerative dementias. We aimed to assess its accuracy in this differential diagnostic context.

METHODS

Plasma t-PrP was measured in 520 individuals including healthy controls (HC) and patients diagnosed with neurological disease control (ND), Alzheimer's disease (AD), sporadic Creutzfeldt-Jakob disease (sCJD), frontotemporal dementia (FTD), Lewy body dementia (LBD) and vascular dementia (VaD). Additionally, t-PrP was quantified in genetic prion diseases and iatrogenic CJD. The accuracy of t-PrP discriminating the diagnostic groups was evaluated and correlated with demographic, genetic and clinical data in prion diseases. Markers of blood-brain barrier impairment were investigated in sCJD brains.

RESULTS

Compared to HC and ND, elevated plasma t-PrP concentrations were detected in sCJD, followed by FTD, AD, VaD and LBD. In sCJD, t-PrP was associated neither with age nor sex, but with codon 129 PRNP genotype. Plasma t-PrP concentrations correlated with cerebrospinal fluid (CSF) markers of neuro-axonal damage, but not with CSF t-PrP. In genetic prion diseases, plasma t-PrP was elevated in all type of mutations investigated. In sCJD brain tissue, extravasation of immunoglobulin G and the presence of swollen astrocytic end-feet around the vessels suggested leakage of blood-brain barrier as a potential source of increased plasma t-PrP.

CONCLUSIONS

Plasma t-PrP is elevated in prion diseases regardless of aetiology. This pilot study opens the possibility to consider plasma t-PrP as a promising blood-based biomarker in the diagnostic of prion disease.

Axonal changes in experimental prion diseases recapitulate those following constriction of postganglionic branches of the superior cervical ganglion: a comparison 40 years later

The major neurological feature of prion diseases is a neuronal loss accomplished through either apoptosis or autophagy. In this review, I compared axonal alterations in prion diseases to those described 40 years earlier as a result of nerve ligation. I also demonstrated that autophagic vacuoles and autophagosomes are a major part of dystrophic neurites. Furthermore, I summarized the current status of the autophagy in prion diseases and hypothesize, that spongiform change may originate from the autophagic vacuoles. This conclusion should be supported by other methods, in particular laser confocal microscopy.

We observed neuronal autophagic vacuoles in different stages of formation, and our interpretation of the ‘maturity’ of their formation may or may not equate to actual developmental stages. Initially, a part of the neuronal cytoplasm was sequestrated within double or multiple membranes (phagophores) and often exhibited increased electron-density. The intracytoplasmic membranes formed labyrinth-like structures that suggest a multiplication of those membranes. The autophagic vacuoles then expand and eventually, a vast area of the cytoplasm was transformed into a merging mass of autophagic vacuoles. Margaret R. Matthews published a long treatise in the Philosophical Transactions of the Royal Society of London in which she had described in great detail the ultrastructure of postganglionic branches of the superior cervical ganglion in the rat following ligation of them. The earliest changes observed by Matthews between 6 h to 2 days in the proximal stump were distensions of proximal axons. Analogously, in our models, an increased number of ‘regular’ (round) and ‘irregular’ MVB and some autophagic vacuoles were observed collectively, both processes were similar.

Sensitive detection of FGFR1 N546K mosaic mutation in patient with encephalocraniocutaneous lipomatosis and pilocytic astrocytoma

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous disorder, with only about 100 cases reported worldwide. It is characterized by congenital lesions of the eye, skin, and central nervous system. Only recently, potential causative FGFR1 point mutations have been identified in brain tumors and cultured skin biopsies from patients with this condition. Here, we analyzed the molecular status of a patient with ECCL and a coexisting pilocytic astrocytoma with detected FGFR1 N546K mutation. The presence of the alteration in both affected and unaffected tissues has been evaluated using Sanger sequencing and droplet digital polymerase chain reaction (ddPCR) technique. The ddPCR analysis showed differential distribution of the alteration in all specimens, including unaffected and untreated samples. Therefore, we confirm that FGFR1 N546K is a plausible causative mutation of ECCL patients and could be associated with a risk of brain tumor development. We also show the usefulness of sensitive ddPCR method for detection of low levels of autosomal mosaic mutation in blood or swabs. We suggest that utilization of this method may improve the diagnostic process, especially when targeted therapies are considered.

Expression-based decision tree model reveals distinct microRNA expression pattern in pediatric neuronal and mixed neuronal-glial tumors

Background

The understanding of the molecular biology of pediatric neuronal and mixed neuronal-glial brain tumors is still insufficient due to low frequency and heterogeneity of those lesions which comprise several subtypes presenting neuronal and/or neuronal-glial differentiation. Important is that the most frequent ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) showed limited number of detectable molecular alterations. In such cases analyses of additional genomic mechanisms seem to be the most promising. The aim of the study was to evaluate microRNA (miRNA) profiles in GGs, DNETs and pilocytic asytrocytomas (PA) and test the hypothesis of plausible miRNA connection with histopathological subtypes of particular pediatric glial and mixed glioneronal tumors.

Methods

The study was designed as the two-stage analysis. Microarray testing was performed with the use of the miRCURY LNA microRNA Array technology in 51 cases. Validation set comprised 107 samples used during confirmation of the profiling results by qPCR bioinformatic analysis.

Results

Microarray data was compared between the groups using an analysis of variance with the Benjamini-Hochberg procedure used to estimate false discovery rates. After filtration 782 miRNAs were eligible for further analysis. Based on the results of 10 × 10-fold cross-validation J48 algorithm was identified as the most resilient to overfitting. Pairwise comparison showed the DNETs to be the most divergent with the largest number of miRNAs differing from either of the two comparative groups. Validation of array analysis was performed for miRNAs used in the classification model: miR-155-5p, miR-4754, miR-4530, miR-628-3p, let-7b-3p, miR-4758-3p, miRPlus-A1086 and miR-891a-5p. Model developed on their expression measured by qPCR showed weighted AUC of 0.97 (95% CI for all classes ranging from 0.91 to 1.00). A computational analysis was used to identify mRNA targets for final set of selected miRNAs using miRWalk database. Among genomic targets of selected molecules ZBTB20, LCOR, PFKFB2, SYNJ2BP and TPD52 genes were noted.

Conclusions

Our data showed the existence of miRNAs which expression is specific for different histological types of tumors. miRNA expression analysis may be useful in in-depth molecular diagnostic process of the tumors and could elucidate their origins and molecular background.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5739-5) contains supplementary material, which is available to authorized users.

Morphometric analysis of mitochondria in lymphocytes of patients with exacerbations of chronic obstructive pulmonary disease - pilot study

Introduction

Exacerbations of chronic obstructive pulmonary disease (ECOPD) are important events in the course of the disease, negatively influencing health status and disease progression. Therefore, there is a strong need for deeper understanding of the pathology of ECOPD to elaborate new therapeutic approaches and ameliorate prognoses. Contributions of mitochondria to pathobiology of COPD are still under investigation, although growing evidence suggests their important role in this disease. The aim of our study was to assess the morphometric parameters of mitochondria in lymphocytes of patients with ECOPD.

Patients and methods

Lymphocytes were isolated from the peripheral blood of patients with COPD. Transmission electron microscopy was used to assess absolute number of mitochondria per cell, mitochondrial content, and morphometric parameters of individual mitochondria. We also counted indexes for elongation and interconnectivity.

Results

Eighteen patients (9 with ECOPD and 9 in the stable period of the disease) were analyzed. We observed significantly lower length of mitochondrion (P=0.03) and significant decrease both in elongation (P=0.03) and interconnectivity indexes (P=0.04) in ECOPD patients.

Conclusions

The morphometric parameters of mitochondria in lymphocytes derived from patients during the early period of ECOPD requiring hospitalization are altered in comparison to patients in the stable period of the disease. This suggests their contribution to pathobiology of ECOPD. These preliminary outcomes should be further validated in larger size samples.

Altered MicroRNA Expression Is Associated with Tumor Grade, Molecular Background and Outcome in Childhood Infratentorial Ependymoma

Background

Ependymal tumors are the third most common group of brain tumors in children, accounting for about 10% of all primary brain neoplasms. According to the current WHO classification, they comprise four entities with the most frequent ependymoma and anaplastic ependymoma. The most of pediatric tumors are located within the posterior fossa, with a tendency to infiltrate the vital brain structures. This limits surgical resection and poses a considerable clinical problem. Moreover, there are no appropriate outcome prognostic factors besides the extent of surgical resection. Despite definition of molecular subgroups, the majority of childhood ependymomas present a balanced genome, which makes it difficult to establish molecular prognostic factors.

Methods

The purpose of our study was to explore whether miRNA expression could be used as prognostic markers in pediatric infratentorial ependymomas. We also performed a mRNA expression pattern analysis of NELL2 and LAMA2 genes, with immunohistochemical illustrations of representative cases. The miRNA and mRNA expression was measured in 53 pediatric infratentorial ependymomas using a real-time quantitative PCR.

Results

Three miRNAs were shown to efficiently differentiate between grade II and III ependymomas: miR-17-5p, miR-19a-3p, and miR-106b-5p. Survival analysis showed that the probabilities of overall (p = 0.036) and event-free survival (p = 0.002) were reduced with higher than median miRNA expression levels of miR-17-5p. Using multivariate analysis adjusted for patient's age, sex, tumor grade and localization, we showed statistically significant associations with event-free survival (p = 0004) and borderline statistical significance with overall survival (p = 0.057) for miR-17-5p. Correlation analysis of miR-19a, miR-17-5p, miR-106b revealed that their expression levels were significantly correlated with EZH2 expression, suggested marker of PFA ependymomas. Furthermore, lower expression level of LAMA2 mRNA was shown to be associated with an increased risk of death in covariate-adjusted analyses.

Conclusions

Our data provide a better understanding of pediatric ependymoma and suggests the presence of plausible molecular biomarkers connected with the outcome.

Isolation and partial characterization of a highly divergent lineage of hantavirus from the European mole (Talpa europaea)

Genetically distinct hantaviruses have been identified in five species of fossorial moles (order Eulipotyphla, family Talpidae) from Eurasia and North America. Here, we report the isolation and partial characterization of a highly divergent hantavirus, named Nova virus (NVAV), from lung tissue of a European mole (Talpa europaea), captured in central Poland in August 2013. Typical hantavirus-like particles, measuring 80-120 nm in diameter, were found in NVAV-infected Vero E6 cells by transmission electron microscopy. Whole-genome sequences of the isolate, designated NVAV strain Te34, were identical to that amplified from the original lung tissue, and phylogenetic analysis of the full-length L, M and S segments, using maximum-likelihood and Bayesian methods, showed that NVAV was most closely related to hantaviruses harbored by insectivorous bats, consistent with an ancient evolutionary origin. Infant Swiss Webster mice, inoculated with NVAV by the intraperitoneal route, developed weight loss and hyperactivity, beginning at 16 days, followed by hind-limb paralysis and death. High NVAV RNA copies were detected in lung, liver, kidney, spleen and brain by quantitative real-time RT-PCR. Neuropathological examination showed astrocytic and microglial activation and neuronal loss. The first mole-borne hantavirus isolate will facilitate long-overdue studies on its infectivity and pathogenic potential in humans.

Transcriptional profiles of pilocytic astrocytoma are related to their three different locations, but not to radiological tumor features

Background

Pilocytic astrocytoma is the most common type of brain tumor in the pediatric population, with a generally favorable prognosis, although recurrences or leptomeningeal dissemination are sometimes also observed. For tumors originating in the supra-or infratentorial location, a different molecular background was suggested, but plausible correlations between the transcriptional profile and radiological features and/or clinical course are still undefined. The purpose of this study was to identify gene expression profiles related to the most frequent locations of this tumor, subtypes based on various radiological features, and the clinical pattern of the disease.

Methods

Eighty six children (55 males and 31 females) with histologically verified pilocytic astrocytoma were included in this study. Their age at the time of diagnosis ranged from fourteen months to seventeen years, with a mean age of seven years. There were 40 cerebellar, 23 optic tract/hypothalamic, 21 cerebral hemispheric, and two brainstem tumors. According to the radiological features presented on MRI, all cases were divided into four subtypes: cystic tumor with a non-enhancing cyst wall; cystic tumor with an enhancing cyst wall; solid tumor with central necrosis; and solid or mainly solid tumor. In 81 cases primary surgical resection was the only and curative treatment, and in five cases progression of the disease was observed. In 47 cases the analysis was done by using high density oligonucleotide microarrays (Affymetrix HG-U133 Plus 2.0) with subsequent bioinformatic analyses and confirmation of the results by independent RT-qPCR (on 39 samples).

Results

Bioinformatic analyses showed that the gene expression profile of pilocytic astrocytoma is highly dependent on the tumor location. The most prominent differences were noted for IRX2, PAX3, CXCL14, LHX2, SIX6, CNTN1 and SIX1 genes expression even within different compartments of the supratentorial region. Analysis of the genes potentially associated with radiological features showed much weaker transcriptome differences. Single genes showed association with the tendency to progression.

Conclusions

Here we have shown that pilocytic astrocytomas of three different locations can be precisely differentiated on the basis of their gene expression level, but their transcriptional profiles does not strongly reflect the radiological appearance of the tumor or the course of the disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1810-z) contains supplementary material, which is available to authorized users.

I716F AβPP mutation associates with the deposition of oligomeric pyroglutamate amyloid-β and α-synucleinopathy with Lewy bodies

Autosomal dominant familial Alzheimer's disease (AD) is associated with mutations in the AβPP, PSEN1, and PSEN2 genes. The clinical phenotype associated with AβPP mutations is mainly characterized by dementia or by strokes related to cerebral amyloid angiopathy (CAA). We present a comprehensive clinical, neuropathological, genetic, and biochemical study on a patient affected by familial AD associated with the I716F mutation in the AβPP gene. The clinical phenotype was characterized by early age of onset of 47 years, and rapidly progressive cerebellar ataxia, myoclonic jerks, rigidity, and dementia reminiscent of Creutzfeldt-Jakob disease (CJD), followed by a prolonged persistent vegetative state. Neuropathological evaluation of the proband revealed AD-related pathology but also α-synucleinopathy compatible with dementia with Lewy bodies neocortical stage or Parkinson's disease corresponding to Braak stage 6. Tau-pathology in the form of neurofibrillary degeneration corresponded to stage VI according to the Braak classification. The severe Aβ pathology included CAA, numerous plaques, and deposition of N-truncated pyroglutamate-modified Aβ peptides. Remarkably, pyroglutamate Aβ oligomers were also present intracellularly in Purkinje cells corresponding to the ataxic phenotype. The detection of a CJD-like phenotype expands the spectrum of clinical presentations associated with familial AD. Our study supports the concept that the neuropathology of familial AD expands beyond the classical AD-related pathology as defined by plaques and tangles. Finally, we provide evidence for the first time that oligomeric pyroglutamate Aβ is present in a specific pattern correlating with the clinical symptoms of a patient with AβPP I716F mutation.

Co-circulation of soricid- and talpid-borne hantaviruses in Poland

Previously, we reported the discovery of a genetically distinct hantavirus, designated Boginia virus (BOGV), in the Eurasian water shrew (Neomys fodiens), as well as the detection of Seewis virus (SWSV) in the Eurasian common shrew (Sorex araneus), in central Poland. In this expanded study of 133 shrews and 69 moles captured during 2010-2013 in central and southeastern Poland, we demonstrate the co-circulation of BOGV in the Eurasian water shrew and SWSV in the Eurasian common shrew, Eurasian pygmy shrew (Sorex minutus) and Mediterranean water shrew (Neomys anomalus). In addition, we found high prevalence of Nova virus (NVAV) infection in the European mole (Talpa europaea), with evidence of NVAV RNA in heart, lung, liver, kidney, spleen and intestine. The nucleotide and amino acid sequence variation of the L segment among the SWSV strains was 0-18.8% and 0-5.4%, respectively. And for the 38 NVAV strains from European moles captured in Huta Dłutowska, the L-segment genetic similarity ranged from 94.1%-100% at the nucleotide level and 96.3%-100% at the amino acid level. Phylogenetic analyses showed geographic-specific lineages of SWSV and NVAV in Poland, not unlike that of rodent-borne hantaviruses, suggesting long-standing host-specific adaptation. The co-circulation and distribution of BOGV, SWSV and NVAV in Poland parallels findings of multiple hantavirus species co-existing in their respective rodent reservoir species elsewhere in Europe. Also, the detection of SWSV in three syntopic shrew species resembles spill over events observed among some rodent-borne hantaviruses.

Melatonin-induced glycosaminoglycans augmentation in myocardium remote to infarction

Elevated levels of collagen as well as transient increases of glycosaminoglycans (GAG) have been shown in the myocardium remote to the infarction. The aim of the study is to observe the effect of melatonin on the accumulation of collagen and GAG in the left ventricle wall, remote to the infarction. A second aim is to determine whether the effect of the pineal indole is mediated by the membrane melatonin receptors of heart fibroblasts. Rats with myocardial infarction induced by ligation of the left coronary artery were treated with melatonin at a dose of 60 μg/100 g b.w. or vehicle (2% ethanol in 0.9% NaCl). The results were compared with an untreated control. In the second part of the study, the fibroblasts from the non-infarcted part of myocardium were isolated and cultured. Melatonin at a range of concentrations from 10(-8) M to 10(-6) M was applied to the fibroblast cultures. In the final part of the study, the influence of luzindole (10(-6) M), the melatonin membrane receptor inhibitor, on melatonin-induced GAG augmentation was investigated. Both collagen and GAG content were measured in the experiment. Melatonin elevated GAG content in the myocardium remote to the infarcted heart. Collagen level was not changed by pineal indoleamine. Fibroblasts isolated from the myocardium varied in shape from fusiform to spindle-shaped. Moreover, the pineal hormone (10(-7)M and 10(-6)M) increased GAG accumulation in the fibroblast culture. Luzindole inhibited melatonin-induced elevation of GAG content at 10(-6)M. Melatonin increased GAG content in the myocardium remote to infarction. This effect was dependent on the direct influence of the pineal indole on the heart fibroblasts. The melatonin-induced GAG elevation is blocked by luzindole, the melatonin membrane receptors inhibitor, indicating a direct effect of this indole.

Screening for EGFR amplifications with a novel method and their significance for the outcome of glioblastoma patients

Glioblastoma is a highly aggressive tumour of the central nervous system, characterised by poor prognosis irrespective of the applied treatment. The aim of our study was to analyse whether the molecular markers of glioblastoma (i.e. TP53 and IDH1 mutations, CDKN2A deletion, EGFR amplification, chromosome 7 polysomy and EGFRvIII expression) could be associated with distinct prognosis and/or response to the therapy. Moreover, we describe a method which allows for a reliable, as well as time- and cost-effective, screening for EGFR amplification and chromosome 7 polysomy with quantitative Real-Time PCR at DNA level. In the clinical data, only the patient’s age had prognostic significance (continuous: HR = 1.04; p<0.01). At the molecular level, EGFRvIII expression was associated with a better prognosis (HR = 0.37; p = 0.04). Intriguingly, EGFR amplification was associated with a worse outcome in younger patients (HR = 3.75; p<0.01) and in patients treated with radiotherapy (HR = 2.71; p = 0.03). We did not observe any difference between the patients with the amplification treated with radiotherapy and the patients without such a treatment. Next, EGFR amplification was related to a better prognosis in combination with the homozygous CDKN2A deletion (HR = 0.12; p = 0.01), but to a poorer prognosis in combination with chromosome 7 polysomy (HR = 14.88; p = 0.01). Importantly, the results emphasise the necessity to distinguish both mechanisms of the increased EGFR gene copy number (amplification and polysomy). To conclude, although the data presented here require validation in different groups of patients, they strongly advocate the consideration of the patient’s tumour molecular characteristics in the selection of the therapy.

Assessment of OPG/RANK/RANKL gene expression levels in peripheral blood mononuclear cells (PBMC) after treatment with strontium ranelate and ibandronate in patients with postmenopausal osteoporosis

CONTEXT

Recent research results have confirmed the high significance of the OPG/RANK/RANKL system in the development of bone diseases.

AIM

The aim of the reported study was to assess gene expression levels of the OPG/RANK/RANKL system in peripheral blood mononuclear cells (PBMCs) after strontium ranelate (SR) and ibandronate administered to patients with postmenopausal osteoporosis.

PATIENTS AND METHODS

A total of 89 postmenopausal women, aged 51 to 85 years, patients of the Outpatient Clinic of Osteoporosis of the Military Teaching Hospital in Lodz, were enrolled into the study. The patients were randomly assigned to different medical therapies: ibandronate and SR. Patients of the control group received only calcium and vitamin D₃ supplements. Patient visits were repeated after 3 and 6 months. Measurements of serum alkaline phosphatase concentrations and of RNA expression in PBMCs as well as of total serum calcium and phosphate levels and of their 24-hour urine excretion rates were carried out in material, collected at baseline and after 3 and 6 months of the therapy. Densitometry of the left hip and of the lumbar spine was done at the baseline visit and after 6 months.

RESULTS

The differences in gene expressions of RANKL and RANK were not significant during the study period and did not differ between the groups in a statistically significant manner. No OPG gene expression was observed in PBMCs of patients in any of the studied groups and at any time point. The tendency of correlation (P = .07) was observed between decreasing RANK gene expression and increasing bone mineral density in the patients treated with SR.

CONCLUSIONS

Both ibandronate and SR do not seem to cause any significant changes in gene expression levels of OPG/RANK/RANKL in PBMCs during the first 6 months of treatment.

Association between the PRNP 1368 polymorphism and the occurrence of sporadic Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is a rare transmissible neurodegenerative disorder. The etiology of sporadic form of CJD remains unsolved. In addition to the codon 129 polymorphism, polymorphisms in the non-coding region of PRNP are considered as important factors in sCJD development. To assess a possible association between PRNP 1368 SNP and sCJD, we compared the genotype, allele and haplotype frequencies of the 1368 SNP among 46 sCJD patients of Dutch origin with the respective frequencies in healthy controls. We detected a significant association between sCJD and 1368T/T genotype. A significant difference was also observed in 1368 alleles' distribution. In the haplotype analysis, haplotype 1368C-129G was associated with decreased risk of sCJD in Dutch population. Our findings support the hypothesis that genetic variations in the regulatory region of the PRNP gene may influence the pathogenesis of sCJD.

PRND 3'UTR polymorphism may be associated with behavioral disturbances in Alzheimer disease

The etiology of behavioral and psychological symptoms of dementia (BPSD) is complex, including putative biological, psychological, social and environmental factors. Recent years have witnessed accumulation of data on the association between genetic factors and behavioral abnormalities in Alzheimer disease (AD). In this research paper, our aim is to evaluate the association between the APOE, CYP46, PRNP and PRND genes and the profile of neuropsychiatric symptoms in Polish subjects with AD and mild cognitive impairment (MCI). We studied 99 patients with AD and 48 subjects with MCI. The presence and profile of BPSD were evaluated at baseline and prospectively with the Neuropsychiatric Inventory (NPI). Patients were dichotomized into those having ever experienced a particular symptom and those who did not over the whole disease period. Genotyping was performed using previously described standard protocols. The prevalence of comorbid behavioral symptoms and the overall level of behavioral burden were significantly greater in AD compared with the MCI group. In AD patients, carrier status of the T allele of the 3'UTR (untranslated region) PRND polymorphism was associated with an increased cumulative behavioral load and an elevated risk for delusions, anxiety, agitation/aggression, apathy and irritability/emotional ability. Among MCI subjects, APOE ε4 carriers demonstrated a reduced risk for nighttime behavior change. No other statistically significant genotype-phenotype correlations were observed, including the APOE, CYP46 and PRNP genes. A precise estimation of the exact significance of particular polymorphisms in BPSD etiology requires future studies on large populations.

Gerstmann-Sträussler-Scheinker disease

Gerstmann-Sträussler-Scheinker (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. The first "H" family had been known by the Viennese neuropsychiatrists since the XXth century and was reported by Gerstmann, Sträussler and Scheinker in 1936. In this chapter we present the clinical, neuropathological and molecular data on GSS with the mutations in the PRNP gene: at codons 102, 105, 117, 131, 145, 187, 198, 202, 212, 217 and 232. In several families with GSS the responsible mutations are unknown.

Ultrastructure of meningiomas: autophagy is involved in the pathogenesis of "intranuclear vacuoles"

We report here common ultrastructural findings in a short list of meningiomas. At the lower power magnification, a tumour consisted of elongated or round cells and innumerable cellular processes connected with diverse intercellular junctions. Nuclei presented no specific features, nucleoli were infrequently seen and heterochromatin was clumped beneath the nuclear membranes. In a case of clear cell meningioma, cells were of watery cytoplasm. Occasionally, immobile cilia, completely ensheathed by the cytoplasm and anchored by blepharoplasts were seen; as we did not encounter those rare cilia in cross-sections, no further insight into their inner microtubular-doublet structure was possible. The cytoplasm of the cells and the processes were filled with the intermediate filaments. In the intercellular space, collagen fibrils and electron-dense material was occasionally observed. The majority of the tumour samples were filled with processes. Several types of junctional complexes were observed. The most frequent were desmosomes and in the proper plane of section their whole pentalaminar structure was readily discernible. However, robust tonofilaments, as seen in epithelial neoplasms, were not observed. Those desmosomal junctions were either completely symmetric or asymmetric, but the exact symmetry could not be judged without the assistance of a goniometer. Some junctional complexes were more elaborate, with desmosomal junctions separated by a tight apposition of membranes, which suggests tight junctions. "Intranuclear vacuoles" well-visible even at low power were defined as indentation of the cytoplasm into the nucleus. Within these vacuoles, autophagic vacuoles and lysosomal bodies were seen, suggesting an active macroautophagy process. In 2 cases, severe lipidization of meningioma cell cytoplasm was observed. In a case of anaplastic meningioma, a mitotic figure was found. In another case, empty rectangular spaces in the cytoplasm, suggestive of pre-existing crystalloid structures, were seen.

Association of the PRNP regulatory region polymorphisms with the occurrence of sporadic Creutzfeldt-Jakob disease

The prion protein (PrP) plays a central role in the pathogenesis of Creutzfeldt-Jakob disease and other transmissible spongiform encephalopathies (TSEs). Mutations in the coding region of the prion protein (PRNP) gene are linked to inherited forms of TSEs whereas aetiology of sporadic CJD (sCJD) remains obscure. It remains unclear whether the primary DNA sequence at non-coding region of PRNP gene influences development of the sCJD. Several recent reports showed non-coding region polymorphisms associated with sCJD but other could not support those findings. To test the hypothesis that there is a relationship between SNPs polymorphisms of PRNP non-coding regions and susceptibility to sCJD, we compared the primary structure of the regulatory region of the PRNP in 45 Dutch sCJD patients and in 135 healthy controls. We found a significant linkage of +310 C allele (OR 0.27, 95% CI 0.09-0.77; P = 0.009) and +310G/C genotype (OR 0.33, 95% CI 0.11-0.98; P = 0.048) with sCJD. No differences in frequencies of genotypes and allele of -101C/G and +258 G/A polymorphisms were found between sCJD patients and controls. We found two haplotypes protecting from sCJD (C-V in block 1 and G-C in block 2) and one susceptible haplotype for sCJD (G-G in block 2). Our findings support the hypothesis that polymorphism in the regulatory region of the PRNP gene may play an important role in the pathogenesis of sCJD.

Expression of immunohistochemical markers on microglia in Creutzfeldt-Jakob disease and Alzheimer's disease: morphometric study and review of the literature

INTRODUCTION

Microglia are the resident immune cells of the CNS. They are involved in the pathogenesis of diverse neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease, prion diseases as well as multiple sclerosis, amyotrophic lateral sclerosis and AIDS dementia complex. Activated microglia up-regulate many surface receptors such as the major histocompatibility complex (MHC) or complement receptors and secrete a variety of soluble biologically active factors, which are either neurotrophic (e.g. Glia-Derived Neurotrophic Factor [GDNF]) or proinflammatory and neurotoxic (e.g. tumour necrosis factor alpha [TNF-α], interleukin 1β [IL-1β], nitric oxide [NO], superoxide, eicosanoids, quinolinic acid).

AIM

The aim of this work was to assess differences in the expression of microglial markers (ferritin, CD68, and HLA-DR) between AD and Creutzfeldt-Jakob disease (CJD) brains.

MATERIAL AND METHODS

Analyses were performed on 65 slices derived from 26 brains [46 CJD (20 brains), 12 AD (4 brains) and 7 controls (2 brains)]. Slices were labelled immunohistochemically using anti-ferritin, anti-HLA-DR and anti-CD68 antibodies. The nonparametric Mann-Whitney U test was used to assess quantitative differences between groups.

RESULTS

The expression of microglia markers (HLA-DR and CD68) is more noticeable in CJD than in AD or control brains. There is no difference between AD and controls. The latter statement is only true in the case of using HLA-DR or CD-68 labelling. Furthermore, ferritin is not a recommended marker in this context.

CONCLUSIONS

CNS inflammation is more prominent in CJD than in AD or controls. The lack of differences between AD and controls may result from a relatively advanced neurodegeneration in AD brains. In late phases of AD, inflammation is no longer present, in contrast to the early stages of the disease.

Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD), a neurodegenerative disorder that is the commonest form of human prion disease or transmissible spongiform encephalopathies (TSEs). Four types of CJD are known: Sporadic (sCJD), familial or genetic (gCJD); iatrogenic (iCJD) and variant CJD (vCJD). The latter results from transmission of bovine spongiform encephalopathy (BSE) from cattle to humans. The combination of PrP(Sc) peptide (either 21 kDa or 19 kDa) and the status of the codon 129 of the gene (PRNP) encoding for PrP (either Methionine or Valine) is used to classify sCJD into 6 types: MM1 and MV1, the most common; VV2; MV2 (Brownell/Oppenheimer syndrome); MM2; VV1 and sporadic fatal insomnia, in that order of prevalence. Genetic CJD is caused by diverse mutations in the PRNP gene. The neuropathology of CJD consists of spongiform change, astro- and microgliosis and poorly defined neuronal loss. In a proportion of cases, amyloid plaques, like those of kuru, are seen. PrP immunohistochemistry reveals different types of PrP(Sc) deposits - the most common is the synaptic-type, but perivacuolar, perineuronal and plaque-like deposits may be also detected.

Non-human primates in prion research

Prion diseases or transmissible spongiform encephalopathies are neurodegenerative disorders affecting a broad range of mammals including humans. Initially thought to be of viral origin, it became apparent that prion diseases are unique transmissible entities where a misfolded, highly stable conformer (PrPSc) of the host encoded prion protein (PrPC) represents an essential component of infectious "prions". Prion diseases are mainly studied in rodents, yet several scientific breakthroughs in prion research can be attributed to prion research in primates. In this review we summarize and discuss how studies in non-human primates have advanced our knowledge on transmissibility, pathophysiology and tissue tropism of prions. We discuss assets of non-human primate and rodent models of prion disease pointing out alternatives to experiments in primates.

Glioma cells showing IDH1 mutation cannot be propagated in standard cell culture conditions

BACKGROUND

It has recently been reported by several sources that original (i.e., present in vivo) glioma cell phenotypes or genotypes cannot be maintained in vitro. For example, glioblastoma cell lines presenting EGFR amplification cannot be established.

METHODS AND RESULTS

IDH1 sequencing and loss of heterozygosity analysis was performed for 15 surgery samples of astrocytoma and early and late passages of cells derived from those and for 11 archival samples. We were not able to culture tumour cells presenting IDH1 mutations originating from currently proceeded 10 tumours; the same results were observed in 7 samples of archival material.

CONCLUSION

The IDH1 mutation is expected to be almost mutually exclusive with EGFR amplification, so glioma cells with IDH1 mutations seem to represent a new group of tumour cells, which cannot be readily analysed in vitro because of their elimination. The reasons for this intriguing phenomenon should be investigated since its understanding can help to define a new therapeutic approach based on simulating in vivo conditions, responsible for tumour cells elimination in vitro. Moreover, a new model for culturing glioma cells in vitro should be designed since the current one does not provide conditions corresponding to in vivo growth.

Autophagy contributes to widespread neuronal degeneration in hamsters infected with the Echigo-1 strain of Creutzfeldt-Jakob disease and mice infected with the Fujisaki strain of Gerstmann-Sträussler-Scheinker (GSS) syndrome

The authors report here robust autophagy observed by electron microscopy in both the Echigo-1 strain of Creutzfeldt-Jakob disease in hamsters and the Fujisaki strain of Gerstmann-Sträussler-Scheinker disease in mice. In both models, autophagic vacuoles were observed in several cellular compartments. In neuronal cell bodies, autophagic vacuoles of different size were seen. The cytoplasm of some neurons also contained semicircular cisterns equivalent to an early autophasophore. The major target of autophagy was dystrophic neurites, i.e., enlarged neuritic processes--mostly dendrites but also axonal terminals and preterminals. They contained numerous double- or multiple-membrane-bound autophagosomes or autophagolysosomes and large multivesicular bodies. Multivesicular bodies were also observed within autophagic vacuoles, and large multivesicular bodies were seen within synaptic terminals. Some dystrophic neurites was filled almost completely with multivesicular bodies; the latter were occasionally confluent. The authors conclude that autophagy is an important part of neuropathology in prion disease. They also suggest that spongiform vacuoles, a hallmark for the whole group of prion diseases, may in reality originate from autophagic vacuoles.

Analysis of the prognostic significance of selected morphological and immunohistochemical markers in ependymomas, with literature review

AIM

Ependymal tumours are relatively uncommon primary neoplasms of the central nervous system. Histological criteria distinguishing ependymoma and anaplastic ependymoma are not clear-cut and other parameters are required to allow more precise prognostication in these tumours. We analysed the histological and immunohistochemical features of these tumours (Ki-67, cyclin D1, EGFR, hTERT, Olig2) and correlated them with the clinical outcome.

MATERIAL AND METHODS

We analysed 39 patients with grade II ependymoma (30) and anaplastic ependymoma (9). Twenty-eight tumours developed in children and the remaining 11 patients were adults with intracranial and intraspinal tumours. Eighteen patients died during the follow-up period.

RESULTS AND CONCLUSIONS

Overall survival was reduced significantly for paediatric patients and patients with intracranial tumour. High-grade tumours, increased mitotic index and increased cellularity had an unfavourable influence on survival. Other histological parameters such as nuclear atypia, necrosis and microvascular proliferation did not alter the survival rate. Increased Ki-67 and cyclin D1 indices correlated with worse prognosis. Furthermore, any level of cyclin D1 expression in WHO grade II ependymomas was strongly associated with higher risk of death. No correlation was identified between Olig2, EGFR and hTERT expression and the outcome of the patients.

Polycomb genes expression as a predictor of poor clinical outcome in children with medulloblastoma

INTRODUCTION

Medulloblastoma is the most frequent type of embryonal tumor in the pediatric population, accounting for 20-25% of all brain tumors in children. Recently, the suspected contribution of the Polycomb group (PcG) genes in medulloblastoma development was described. PcG genes play an important role in developmental processes; they are also involved in the self-renewal of hematopoietic and neural stem cells as well as in malignant transformation.

PURPOSE

In this study, we evaluated the expression of BMI1and PCGF2, members of family of PcG genes, and their potential target, MYC oncogene, and analyzed their association with demographic and clinical data.

MATERIALS AND METHODS

Thirty-one children (18 males and 13 females, aged from 0.4 to 17 years) with medulloblastoma were included in this study. The gene's expression level was measured by quantitative real-time PCR, obtained using the two-color multiplexing technique.

RESULTS

We found that the higher expression levels of BMI1 and PCGF2 genes were associated with significantly decreased patient survival (p = 0.02 and p = 0.012, respectively). Significant differences between gender were found, with a higher expression level of the PCGF2 gene observed among females (p = 0.02).

CONCLUSION

Our analysis showed correlation between BMI1 and PCGF2 gene's expression and survival in children with medulloblastoma.

Glioblastoma-derived spheroid cultures as an experimental model for analysis of EGFR anomalies

Glioblastoma cell cultures in vitro are frequently used for investigations on the biology of tumors or new therapeutic approaches. Recent reports have emphasized the importance of cell culture type for maintenance of tumor original features. Nevertheless, the ability of GBM cells to preserve EGFR overdosage in vitro remains controversial. Our experimental approach was based on quantitative analysis of EGFR gene dosage in vitro both at DNA and mRNA level. Real-time PCR data were verified with a FISH method allowing for a distinction between EGFR amplification and polysomy 7. We demonstrated that EGFR amplification accompanied by EGFRwt overexpression was maintained in spheroids, but these phenomena were gradually lost in adherent culture. We noticed a rapid decrease of EGFR overdosage already at the initial stage of cell culture establishment. In contrast to EGFR amplification, the maintenance of polysomy 7 resulted in EGFR locus gain and stabilization even in long-term adherent culture in serum presence. Surprisingly, the EGFRwt expression pattern did not reflect the latter phenomenon and we observed no overexpression of the tested gene. Moreover, quantitative analysis demonstrated that expression of the truncated variant of receptor—EGFRvIII was preserved in GBM-derived spheroids at a level comparable to the initial tumor tissue. Our findings are especially important in the light of research using glioblastoma culture as the experimental model for testing novel EGFR-targeted therapeutics in vitro, with special emphasis on the most common mutated form of receptor—EGFRvIII.

Imperfect oligodendrocytic and neuronal differentiation of glioblastoma cells

Previously, we have reported that glioblastoma (GBM) cells can be differentiated into cells showing neuronal, glial and non-neural (mesenchymal) phenotypes. Before the differentiation the GBM cells co-expressed GFAP, CD44, Beta III tubulin, MAP2, Vimentin, Nestin and SOX-2, whereas during the exposure to a neural differentiation medium the differentiation process was arrested at the early stages and the GBM cells presented features of four phenotypes: multi-lineage, non-neural (mesenchymal), intermediate of neuronal cells and glial cells. Currently, we decided to check if changes in expression of: TH (tyrosine hydroxylase, marker of catecholaminergic cells) and GABA (neurotransmitter of GABAergic neurons) and markers of oligodendrocytic cells (O4, CNP) occur during the exposure of GBM cells to the differentiation medium. After exposure to the PDGF alpha and thyroid hormones (oligodendrocytic differentiation medium 10-30 days) features of oligodendrocytic differentiation were presented by 0.2-2.4% of analyzed cells. During the prolonged neural differentiation (GDNF, bFGF 20-30 days) only few cells showed expression of GABA. Moreover, in our cell cultures, there were not cells expressing markers of catecholaminergic neurons - TH. Our work confirmed that the neuronal differentiation of GBM was inhibited at the stage of the neuronal intermediate phenotype. Moreover, we showed that the oligodendrocytic differentiation of GBM cells is very inefficient.

Kuru and D. Carleton Gajdusek: a close encounter

Kuru, the first human transmissible spongiform encephalopathy, was transmitted to chimpanzees by D. Carleton Gajdusek (1923-2008). In this review, I briefly summarize the history of this seminal discovery alongside its epidemiology, clinical picture, neuropathology and molecular genetics. The discovery of kuru opened new windows into the realms of human medicine and was instrumental in the later transmission of Creutzfeldt-Jakob disease as well as the prediction that bovine spongiform encephalopathy would be transmitted to humans. It was one of the greatest discoveries in biomedical sciences of the 20th century.

Transmissible mink encephalopathy - review of the etiology of a rare prion disease

We review here the history, neuropathology, clinical picture and molecular data on transmissible mink encephalopathy (TME). This obscure disease is of utmost importance as it is plausible that it represents a transmission of hidden bovine spongiform encephalopathy (BSE) to mink in the USA. Of special interest is the similarity of L-type of BSE and TME. Furthermore, experimental molecular studies showed the TME strain-specific in vitro conversion in a cell-free system. In addition, we show here for the first time confocal laser microscopy studies of co-localization of PrPd- amyloid plaques and GFAP-expressing astrocytes.

Kuru: its ramifications after fifty years

Kuru was the first human neurodegenerative disease in the group of transmissible spongiform encephalopathies, prion diseases or, in the past, slow unconventional virus diseases. It was reported to Western medicine in 1957 by Gajdusek and Zigas. Kuru was spread by endocannibalism and because of this the ratio of affected women and children to men was excessive. The hallmark of kuru neuropathology is the amyloid plaque. We may speculate what would happen if kuru had not been discovered or did not exist. The infectious nature of Creutzfeldt-Jakob disease (CJD) would probably not have been suspected until the beginning of the variant CJD (vCJD) outbreak in the UK. Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker disease would have remained for decades as obscure neurodegenerations of merely academic interest. The familial forms of CJD would not have benefited from PRNP gene (a gene encoding for prion protein) analysis, but only later would have been studied by linkage analysis and reverse genetics probably. The study of kuru would have probably been of minimal interest to veterinarians and anthropologists until the bovine spongiform encephalopathy (BSE) epidemic began to exert its devastating effect. The discovery of vCJD would have been delayed, as no surveillance would have been initiated for CJD. And perhaps most importantly, the realization of 'protein-misfolding diseases', including not only the neurodegenerative but also an increasing number of non-neurological disorders, would have been delayed by decades.

Pathology and immunocytochemistry of a kuru brain

We report here results of modern staining techniques including anti-prion protein (PrP) immunocytochemistry to a set of archival brain specimens of a 16 year-old male who died from kuru in 1967. Brain suspensions transmitted disease to chimpanzees and New World monkeys. The PrP gene is homozygous for valine at the polymorphic codon 129. Histology shows neuronal loss, spongiform change, and astrogliosis. Lesions are maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, striatum, and thalamus, and are accentuated in middle and deep cerebral cortical layers. PrP accumulates as diffuse synaptic type deposits and mostly unicentric plaques. PrP deposition is maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, basal ganglia, and cerebellar cortex. Plaques are prominent in the striatum, thalamus, and granular layer of cerebellar cortex. Meticulous examination reveals only rare "florid" plaques with surrounding vacuolation. We conclude that 1) pathology including immunomorphology of PrP deposition in this kuru brain is within the lesion spectrum of Creutzfeldt-Jakob disease although plaques are unusually prominent and widespread; 2) kuru does not share the neuropathological hallmarks of the new Creutzfeldt-Jakob disease variant recently reported in the UK and France; 3) topographic prominence of PrP deposition parallels that of spongiform change and/or astrogliosis.

BCR expression is decreased in meningiomas showing loss of heterozygosity of 22q within a new minimal deletion region

Neurofibromin 2 (NF2), located on chromosome arm 22q, has been established as a tumor suppressor gene involved in meningioma pathogenesis. In our study, we investigated 149 meningiomas to determine whether there are additional tumor suppressor genes localized on chromosome 22q, apart from NF2, that might be involved in meningioma pathogenesis. The LOH analysis on chromosome 22q identified two regions of deletion: the first one, which is limited to the NF2 gene locus, and the second one, which is outside this location. The new minimal deletion region (MDR) included the following genes: BCR (breakpoint cluster region), RAB36 (a member of RAS oncogene family), GNAZ [guanine nucleotide binding protein (G protein), alpha-z polypeptide], and RTDR1 (rhabdoid tumor deletion region gene 1). The expression levels of all these genes, including NF2, were subsequently analyzed by quantitative real-time polymerase chain reaction. We observed a significantly lowered expression level of NF2 in meningiomas with 22q loss of heterozygosity (LOH) within NF2 region compared to the one in meningiomas with 22q retention of heterozygosity (ROH, P<0.05). Similarly, BCR showed a significantly lowered expression in meningiomas with 22q LOH within the new MDR compared to cases with 22q ROH (P<0.05). Our data, together with the already published information considering BCR function suggest that BCR can be considered as a candidate tumor suppressor gene localized on chromosome 22q which may be involved in meningioma pathogenesis.

Ultrastructural study of florid plaques in variant Creutzfeldt-Jakob disease: a comparison with amyloid plaques in kuru, sporadic Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker disease

BACKGROUND

Although the histological features of the amyloid plaques in variant Creutzfeldt-Jakob disease (vCJD) are distinct from those in other forms of prion disease [kuru, sporadic Creutzfeldt-Jakob disease (sCJD) and Gerstmann-Sträussler-Scheinker disease (GSS)], their ultrastructural features have only been described in a single case report.

AIMS

To study vCJD plaques systematically and compare them with plaques in kuru, sCJD, GSS and Alzheimer disease (AD).

METHODS

Amyloid plaques were studied by transmission electron microscopy and image analysis in five cases of vCJD, three cases of GSS, two cases of sCJD, one case of kuru and five cases of AD. Immunohistochemistry was performed on paraffin sections from one case of vCJD, two cases of GSS, one case of kuru and two cases of sCJD.

RESULTS

The florid plaques in vCJD were either compact or more diffuse; in both forms, the radiating fibrils were organized into thick 'tongues', in contrast to kuru plaques. Dystrophic neurites (DNs) containing lysosomal electron-dense bodies or vesicles surrounded florid plaques. Microglial cells were found within florid plaques; occasional amyloid fibrils were identified in membrane-bound pockets of microglial cells. In vCJD, there was significant tau immunoreactivity in DNs around florid plaques while, in sCJD, GSS and kuru, minimal tau immunoreactivity was observed around plaques.

CONCLUSIONS

The ultrastructure of the florid plaques and DNs in vCJD is more reminiscent of neuritic plaques in AD than kuru or multicentric plaques. These findings may reflect differences both in the strains of the transmissible agents responsible for these disorders and in host factors.

Elimination of wild-type P53 mRNA in glioblastomas showing heterozygous mutations of P53

We screened 50 glioblastomas for P53 mutations. Five glioblastomas showed heterozygous mutations, while three were putatively heterozygous. Six of these eight glioblastomas showed elimination of wild-type P53 mRNA. These results strongly suggest that some sort of mechanism(s) favouring mutated over wild-type P53 mRNA exists in glioblastoma cells with heterozygous mutations of this gene.

Cell death and autophagy in prion diseases (transmissible spongiform encephalopathies)

Neuronal autophagy, like apoptosis, is one of the mechanisms of programmed cell death. In this review, we summarize current information about autophagy in naturally occurring and experimentally induced scrapie, Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker syndrome against the broad background of neural degenerations in transmissible spongiform encephalopathies (TSEs). Typically a sequence of events is observed: from a part of the neuronal cytoplasm sequestrated by concentric arrays of double membranes (phagophores); through the enclosure of the cytoplasm and membrane proliferation; to a final transformation of the large area of the cytoplasm into a collection of autophagic vacuoles of different sizes. These autophagic vacuoles form not only in neuronal perikarya but also in neurites and synapses. On the basis of ultrastructural studies, we suggest that autophagy may play a major role in transmissible spongiform encephalopathies and may even participate in the formation of spongiform change.

Subependymal plaques in scrapie-affected hamster brains--why are they so different from compact kuru plaques?

We report here routine thin-section and immunogold electron microscopic studies on diffuse plaques in scrapie-affected hamster brains. These plaques were not discernible by routine HE staining. Ultrastructurally, plaques were recognized as areas of low electron density containing haphazardly-oriented fibrils, but not as stellate compact structures typical of mouse scrapie models; hence we labelled them "loose plaques". Following immunohistochemistry at the electron microscopy level, fibrils within plaques were heavily decorated with PrP-conjugated gold particles. Loose plaques were located beneath the basal border of the ependymal cells and around blood vessels in the adjacent subependymal neuropil. When dystrophic neurites containing electron-dense inclusion bodies, some of them autophagic vacuoles [59], were seen within the plaque perimeter, they always remained PrP-negative. Some microglial cells were observed in close contact with PrP-positive plaques, and secondary lysosomes within these cells were heavily decorated with gold particles.

Prion diseases: a riddle wrapped in a mystery inside an enigma

It is now widely accepted that many structurally diverse proteins can misfold and cause so-called "conformational diseases", including the most common neurodegenerations, Alzheimer's disease and Parkinson's disease. The conversion of largely a-helical or random coil proteins into cross-beta-pleated sheet conformations that form first oligomers and then fibrils underlies these disorders. However, this alpha- to beta-structure transition seems to be a generic propensity of all globular proteins, not only those involved in neurodegenerations, not to mention "prion diseases". Metaphorically, all these neurodegenerations are "infectious" in the sense that misfolded beta-sheeted conformers are formed in a nucleation process in which preformed metastable oligomer acts as a seed (a nucleus) to convert a normal into an abnormal protein. However, in none but transmissible spongiform encephalopathies (TSEs) has infectivity in a microbiological sense ever been observed, and even in TSEs the formation of misfolded protein is not necessarily accompanied by the generation of infectivity de novo. Furthermore, certain "prion diseases" are not TSEs but just "proteinopathies" caused by accumulation of abnormally misfolded PrPd. The presence of a massive amount of PrP-amyloid and no infectivity casts doubts on whether TSEs are really infectious amyloidoses. The misfolding of PrP may yet prove to be an epiphenomenon secondary to infection with a still unknown infectious agent. If, on the other hand, the purely proteinaceous character of the replicating unit of TSE infectivity is ultimately found to be correct, the critical issues become 1) the mechanism by which a misfolded PrP template induces normal protein molecules to adopt the same pathologically misfolded conformation, and 2) the intracellular conditions that are responsible for strain differences in these molecules.

Kuru-fifty years later

Kuru, the first human neurodegenerative disease classified as a transmissible spongiform encephalopathy, prion disease or, in the past, slow unconventional virus disease, was first reported to Western medicine in 1957 by D. Carleton Gajdusek and Vincent Zigas. Thus, this year marks the 50th anniversary of kuru discovery, highlighted by the symposium The end of kuru: 50 years of research into an extraordinary disease organized by John Collinge and Michael Alpers at the Royal Society, London, November 11-12, 2007. In this review, we summarize some data on the epidemiology, neuropathology and clinical picture of kuru.

Phenotype of the DYT1 mutation in the TOR1A gene in a Polish population of patients with dystonia. A preliminary report

BACKGROUND AND PURPOSE

DYT1 dystonia is the most common form of inherited primary dystonia. The aim of the study was: 1) to evaluate the prevalence of the DYT1 mutation in a population of Polish patients with early-onset generalized dystonia and with other forms of familial dystonia, 2) to evaluate the frequency of the DYT1 mutation in patients with writer's cramp, 3) to characterize the phenotype of the DYT1 mutation in the Polish population, and 4) to define the group of patients in whom genetic testing is recommended.

MATERIAL AND METHODS

The following groups of patients were included in the study: 1) patients with early-onset (<30 years) generalized dystonia and those patients with onset after age 30 years who have relatives with early-onset dystonia, 2) patients with writer's cramp (focal or as part of segmental dystonia) independently of age of onset, 3) asymptomatic (adult only) relatives of the diagnosed DYT1 carriers. Genetic tests were performed in 63 subjects---28 sporadic cases of dystonia, 20 patients with familial dystonia, and 15 asymptomatic relatives of patients with confirmed DYT1 mutation.

RESULTS

The DYT1 mutation was found in 17 subjects--10 patients with dystonia and 7 asymptomatic relatives (from 6 families). In all mutation carriers dystonia occurred in one limb before age 26 years. In 8 patients, generalization of dystonia was observed and in 2 cases it remained in a focal form.

CONCLUSIONS

1. The prevalence of DYT1 mutation among patients with early-onset (<or= 24 years) dystonia was 20.8% and it was similar to that found in other European populations. 2. No DYT1 mutation was found among sporadic cases of writer's cramp. 3. In the studied group the most common was the phenotype with early onset (<or= 24 years) and the first symptoms localized in one of the limbs. 4. The obtained results confirm that the recommendations available in the literature concerning DYT1 genetic testing can be applied to the Polish population.

Diverse molecular pattern in a bihemispheric glioblastoma (butterfly glioma) in a 16-year-old boy

Glioblastoma multiforme (GBM), the most common malignant brain tumor of adults, is relatively rare in children. In a GBM affecting a 16-year-old boy, the tumor spread across the corpus callosum (butterfly glioma). This type of bilateral hemispheric growth has previously been thought to result from spread along the white matter tracts. Two samples obtained from opposite sides of the same tumor were analyzed comprehensively for loss of heterozygosity (LOH) and microsatellite instability (MSI). Amplification of EGFR and MDM2 was studied by means of multiplex polymerase chain reaction. Exons 5, 6, 7, and 8 of TP53 were screened for mutations by sequencing. In neither specimen were molecular alterations found in the EGFR, MDM2, or TP53 genes. The specimen obtained from the right hemisphere exhibited a high level of MSI and LOH in chromosome arms 5q, 9p, and 13q. The specimen from the left hemisphere exhibited LOH in chromosome arms 3p, 5q, 9p, 9q, 10p, 10q, and 13q. Here we propose four plausible hypothetical scenarios underlying the tumorigenesis of this GBM.

Disease-specific particles without prion protein in prion diseases - phenomenon or epiphenomenon?

The search for the cause of transmissible spongiform encephalopathies (TSEs) has a long and tortuous history. In a recent paper, 25-nm virus-like particles were identified that were consistently observed in cell cultures infected with Creutzfeldt-Jakob disease (CJD) and scrapie; they are similar to, or even identical with, the virus-like tubulovesicular structures (TVS) found in experimental scrapie as early as in 1968, and subsequently in all naturally occurring and experimentally induced TSEs. These particles have been viewed with caution by the scientific community because of the unverified or uninterpretable record of virus-like structures reported over the years in TSEs. TVS are spherical or tubular particles of approximate diameter 25-37 nm. They are smaller than synaptic vesicles, but larger than many particulate structures of the central nervous system, such as glycogen granules. Their electron density is higher compared with synaptic vesicles, and in experimental murine scrapie, they form paracrystalline arrays. None of these observations distinguish between TVS as an entity critical to the infectious process, or as a highly specific ultrastructural epiphenomenon, but their consistent presence in all TSEs demands further research.

[Significance and prospects of study on molecular alterations in oligodendrogliomas]

Oligodendroglial tumours represent a type of tumours in which molecular alterations may become a significant prognostic factor. During the last decade, enormous progress in understanding of these alterations has been accomplished. Oligodendrogliomas show distinct genetic alterations, allowing us to distinguish them from other types of gliomas. The loss of heterozygosity (LOH) on chromosomes 1p and 19q were reported to be the most frequently observed alterations. While loss of heterozygosity on chromosome 1p is a statistically significant predictor of chemosensitivity, combination with deletions on chromosome 19q was reported to be associated with both chemosensitivity and longer recurrence-free survival after therapy. Conversely, allelic loss on chromosome 10q, observed in many anaplastic oligodendrogliomas, predicts rather poor outcome. The present paper is a compilation of the newest information on the characteristics of the genetic alterations related to the clinical course of oligodendrogliomas, which seems to be important for the proper diagnostics and selection of the appropriate methods of treatment.