Epidemiology of Viliuisk encephalomyelitis in Eastern Siberia.

Background: Viliuisk encephalomyelitis is a disorder that starts, in most cases, as an acute meningoencephalitis. Survivors of the acute phase develop a slowly progressing neurologic syndrome characterized by dementia, dysarthria, and spasticity. An epidemic of this disease has been spreading throughout the Yakut Republic of the Russian Federation.

A proposal for new criteria for the classification of hantaviruses, based on S and M segment protein sequences.

Hantaviruses, members of the family Bunyaviridae, are the causative agents of hemorrhagic fever with renal syndrome and hantavirus cardiopulmonary syndrome. Hantaviruses are currently demarcated into species based on the guidelines provided by the International Committee on Taxonomy of Viruses (ICTV). These guidelines however, are often ignored by the descriptors of novel hantaviruses.

Review. Kuru and its contribution to medicine.

The solution of kuru led us to the solution of Creutzfeldt-Jakob disease and to the elucidation, in humans and other species, of previously unknown mechanisms of infection. These require very close three-dimensional matching, which determines infectious nucleant or prion activity. Evidence for nucleation processes is found widely in the organic and inorganic worlds and in the interactions between them: in the formation of amyloid fibrils; in the biochemistry of silicon; in cave formations deep in the Earth; and in outer space.

Family clustering of Viliuisk encephalomyelitis in traditional and new geographic regions.

Viliuisk encephalomyelitis is an acute, often fatal, meningoencephalitis that tends to develop into a prolonged chronically progressive panencephalitis. Clinical, neuropathologic, and epidemiologic data argue for an infectious cause, although multiple attempts at pathogen isolation have been unsuccessful. To assess mechanisms of disease transmission and spread, we studied 6 multiplex families.

Infectivity studies of both ash and air emissions from simulated incineration of scrapie-contaminated tissues.

We investigated the effectiveness of 15 min exposures to 600 and 1000 degrees C in continuous flow normal and starved-air incineration-like conditions to inactivate samples of pooled brain macerates from hamsters infected with the 263K strain of hamster-adapted scrapie with an infectivity titer in excess of 10(9) mean lethal doses (LD50) per g. Bioassays of the ash, outflow tubing residues, and vented emissions from heating 1 g of tissue samples yielded a total of two transmissions among 21 inoculated animals from the ash of a single specimen burned in normal air at 600 degrees C. No other ash, residue, or emission from samples heated at either 600 or 1000 degrees C, under either normal or starved-air conditions, transmitted disease.

Genetic studies in relation to kuru: an overview.

Kuru is a subacute neurodegenerative disease presenting with limb ataxia, dysarthria, and a shivering tremor. The disease progress to complete motor and mental incapacity and death within 6 to 24 months. Neuropathologically, a typical pattern of neuronal loss, astrocytic and microglial proliferation, characteristic "kuru-type" amyloid plaques, and PrP deposits in the cerebral cortex and cerebellum are observed.

Neuronal cell death in transmissible spongiform encephalopathies (prion diseases) revisited: from apoptosis to autophagy.

Neuronal autophagy, like apoptosis, is one of the mechanisms of the programmed cell death (PCD). In this review, we summarize the presence of autophagic vacuoles in experimentally induced scrapie, Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker (GSS) syndrome. Initially, a part of the neuronal cytoplasm was sequestrated by concentric arrays of double membranes; the enclosed cytoplasm appeared relatively normal except that its density was often increased.

Ultrastructural changes in the optic nerves of rodents with experimental Creutzfeldt-Jakob Disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS) or scrapie.

This report describes the ultrastructural changes in the optic nerves of (1) hamsters infected with the Echigo-1 strain of Creutzfeldt-Jakob disease (CJD), (2) hamsters infected with the 263K or 22C-H strain of scrapie, and (3) mice infected with the Fujisaki strain of Gerstmann-Sträussler-Scheinker disease (GSS). Vacuolation of myelinated fibres was present in the myelin sheaths, with splitting of myelin lamellae. These vacuoles contained typical secondary vacuoles and curled membrane fragments.

Viliuisk encephalomyelitis: intrathecal synthesis of oligoclonal IgG.

Viliuisk encephalomyelitis (VE) is a neurodegenerative disorder expressed as subacute meningo-encephalitis progressing to a more prolonged pan-encephalitic syndrome with a fatal outcome within 1 to 10 years. Some patients survive to a steady state of global dementia and severe spasticity that may last for over 20 years. Multiple micronecrotic foci surrounded by inflammatory infiltrates are observed throughout the cerebral cortex and other gray matter areas.

How do neurons degenerate in prion diseases or transmissible spongiform encephalopathies (TSEs): neuronal autophagy revisited.

As in other neurodegenerative diseases such as Alzheimer's disease, neurons in prion diseases or transmissible spongiform encephalopathies (TSEs) die via programmed cell death of which the apoptotic process is relatively well characterized. A subcellular alteration linked to apoptosis is the formation of autophagic vacuoles, which we and others demonstrated in CJD- and scrapie-affected rodent brains. Autophagy may co-exist with apoptosis or may precede it and the process may be induced by apoptotic stimuli.

Ultrastructural studies of experimental scrapie and Creutzfeldt-Jakob disease in hamsters. II. Astrocytic and macrophage reaction towards axonal destruction.

We report here the microglial (macrophage) and astrocytic reaction in several models of transmissible spongiform encephalopathies (TSEs) or prion diseases. With the low power electron microscopy it was readily apparent that myelinated vacuoles were surrounded by cells and their processes. The latter belonged either to hyperplastic reactive astrocytes or to macrophages.

Ultrastructural studies of experimental scrapie and Creutzfeldt-Jakob disease in hamsters. I. Alterations of myelinated axons.

Classical and ultrastructural neuropathology of prion diseases are generally well described. Here we report that alterations of myelinated fibres in hamsters infected either with polioencephalopathic strains of scrapie or panencephalopathic strains of CJD (Echigo-1) are virtually identical and differ only quantitatively. In contrast, mice infected with the panencephalopathic Fujisaki strain of CJD exhibited much more elaborate changes of myelinated fibres.

A new point mutation of the PRNP gene in Gerstmann-Sträussler-Scheinker case in Poland.

We report here a case of Gerstmann-Sträussler-Scheinker (GSS) disease with a new mutation at the codon 232 (Met to Thr) of the PRNP gene. This case was characterized by PrP-immunopositive kuru and multicentric plaques; these plaques were also seen in the cerebral cortex, hippocampus and in the deep subcortical nuclei. Diffuse PrP depositions were also detected.

Increased susceptibility to Kuru of carriers of the PRNP 129 methionine/methionine genotype.

Kuru reached epidemic proportions by the mid-twentieth century among the Fore people of New Guinea and disappeared after the abolition of cannibalistic rituals. To determine susceptibility to kuru and its role in the spread and elimination of the epidemic, we analyzed the PRNP gene coding sequences in 5 kuru patients; no germline mutations were found. Analysis of the PRNP 129 methionine (M)/valine (V) polymorphism in 80 patients and 95 unaffected controls demonstrated that the kuru epidemic preferentially affected individuals with the M/M genotype.

Progressive muscular atrophy variant of familial amyotrophic lateral sclerosis (PMA/ALS).

Twelve cases of adult-onset progressive muscular atrophy variant of amyotrophic lateral sclerosis (PMA/ALS) were studied in a small rural population of 1500 in the Republic of Belarus (former Soviet Union). The patients were members of three apparently related kindreds, each showing autosomal dominant pattern of disease inheritance. The average age at clinical onset ranged from 26 to 57 years (mean, 40 years).

New studies on the heat resistance of hamster-adapted scrapie agent: threshold survival after ashing at 600 degrees C suggests an inorganic template of replication.

One-gram samples from a pool of crude brain tissue from hamsters infected with the 263K strain of hamster-adapted scrapie agent were placed in covered quartz-glass crucibles and exposed for either 5 or 15 min to dry heat at temperatures ranging from 150 degrees C to 1,000 degrees C. Residual infectivity in the treated samples was assayed by the intracerebral inoculation of dilution series into healthy weanling hamsters, which were observed for 10 months; disease transmissions were verified by Western blot testing for proteinase-resistant protein in brains from clinically positive hamsters. Unheated control tissue contained 9.

Movement disorders in Kuru.

Objective: To describe the gamut of movement disorders (MD) seen during the clinical course of kuru.

Background: Kuru is a subacute spongiform encephalopathy that was confined to several adjacent cultures in the Eastern Highlands of New Guinea and resulted from contamination with brain tissue during the ritual endocannibalism practiced in those societies. This unique neurologic disease was recorded extensively with film between 1957 and 1976, and these comprehensive research documents have been donated to the American Academy of Neurology archives by one of the authors (DCG).

Natural and experimental oral infection of nonhuman primates by bovine spongiform encephalopathy agents.

Experimental lemurs either were infected orally with the agent of bovine spongiform encephalopathy (BSE) or were maintained as uninfected control animals. Immunohistochemical examination for proteinase-resistant protein (prion protein or PrP) was performed on tissues from two infected but still asymptomatic lemurs, killed 5 months after infection, and from three uninfected control lemurs. Control tissues showed no staining, whereas PrP was detected in the infected animals in tonsil, gastrointestinal tract and associated lymphatic tissues, and spleen.

Ancestral origins and worldwide distribution of the PRNP 200K mutation causing familial Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) belongs to a group of prion diseases that may be infectious, sporadic, or hereditary. The 200K point mutation in the PRNP gene is the most frequent cause of hereditary CJD, accounting for >70% of families with CJD worldwide. Prevalence of the 200K variant of familial CJD is especially high in Slovakia, Chile, and Italy, and among populations of Libyan and Tunisian Jews.

A case of sporadic Creutzfeldt-Jakob disease with a Gerstmann-Sträussler-Scheinker phenotype but no alterations in the PRNP gene.

We report here an unusual sporadic case of Creutzfeldt-Jakob disease (CJD) characterized by an abundance of prion protein (PrP)-immunopositive kuru and multicentric but not florid plaques. Molecular genetic analysis of the PRNP open reading frame region spanning codons 8-221 was performed. Neither deletion nor insertion mutations were detected in the repeat area of the PRNP.

Phenotype-genotype studies in kuru: implications for new variant Creutzfeldt-Jakob disease.

The PRNP polymorphic (methionine/valine) codon 129 genotype influences the phenotypic features of transmissible spongiform encephalopathy. All tested cases of new variant Creutzfeldt-Jakob disease (nvCJD) have been homozygous for methionine, and it is conjectural whether different genotypes, if they appear, might have distinctive phenotypes and implications for the future "epidemic curve" of nvCJD. Genotype-phenotype studies of kuru, the only other orally transmitted transmissible spongiform encephalopathy, might be instructive in predicting the answers to these questions.

Phenotypic variability of Gerstmann-Sträussler-Scheinker disease is associated with prion protein heterogeneity.

Gerstmann-Sträussler-Scheinker disease (GSS), a cerebello-pyramidal syndrome associated with dementia and caused by mutations in the prion protein gene (PRNP), is phenotypically heterogeneous. The molecular mechanisms responsible for such heterogeneity are unknown. Since we hypothesize that prion protein (PrP) heterogeneity may be associated with clinico-pathologic heterogeneity, the aim of this study was to analyze PrP in several GSS variants.

The distribution of infectivity in blood components and plasma derivatives in experimental models of transmissible spongiform encephalopathy.

Background: The administration of blood components from donors who subsequently develop Creutzfeldt-Jakob disease has raised the issue of blood as a possible vehicle for iatrogenic disease.

Study Design And Methods: We examined infectivity in blood components and Cohn plasma fractions in normal human blood that had been "spiked" with trypsinized cells from a scrapie-infected hamster brain, and in blood of clinically ill mice that had been inoculated with a mouse-adapted strain of human transmissible spongiform encephalopathy. Infectivity was assayed by intracerebral inoculation of the blood specimens into healthy animals.