Showing papers by "Herbert Budka published in 2010"

Recombinant prion protein induces a new transmissible prion disease in wild-type animals

Abstract: Prion disease is a neurodegenerative malady, which is believed to be transmitted via a prion protein in its abnormal conformation (PrPSc). Previous studies have failed to demonstrate that prion disease could be induced in wild-type animals using recombinant prion protein (rPrP) produced in Escherichia coli. Here, we report that prion infectivity was generated in Syrian hamsters after inoculating full-length rPrP that had been converted into the cross-β-sheet amyloid form and subjected to annealing. Serial transmission gave rise to a disease phenotype with highly unique clinical and neuropathological features. Among them were the deposition of large PrPSc plaques in subpial and subependymal areas in brain and spinal cord, very minor lesioning of the hippocampus and cerebellum, and a very slow progression of disease after onset of clinical signs despite the accumulation of large amounts of PrPSc in the brain. The length of the clinical duration is more typical of human and large animal prion diseases, than those of rodents. Our studies establish that transmissible prion disease can be induced in wild-type animals by inoculation of rPrP and introduce a valuable new model of prion diseases. Electronic supplementary material The online version of this article (doi:10.1007/s00401-009-0633-x) contains supplementary material, which is available to authorized users.

EFSA Panel on Biological Hazards; Scientific Opinion on a Quantitative Microbiological Risk Assessment of Salmonella in slaughter and breeder pigs

Abstract: This Quantitative Microbiological Risk Assessment (QMRA) represents a major step forward in terms of modelling Salmonella in pigs from farm to consumption as it takes into account the variability between and within EU Member States (MSs). Around 10-20% of human Salmonella infections in EU may be attributable to the pig reservoir as a whole. From the QMRA analysis it appears that an 80% or 90% reduction of lymph node prevalence should result in a comparable reduction in the number of human cases attributable to pig meat products. Theoretically, according to the QMRA the following scenarios appear possible (a) by ensuring that breeder pigs are Salmonella-free a reduction of 70-80% in high prevalence MSs and 10-20% in low prevalence MSs can be foreseen; (b) by feeding only Salmonella-free feedstuffs, a reduction of 10-20% in high prevalence MSs and 60-70% in low prevalence MSs can be foreseen; and (c) by preventing infection from external sources of Salmonella (i.e. rodents and birds) a reduction of 10-20% in slaughter pig lymph node prevalence can be foreseen in both high and low prevalence MSs. A hierarchy of control measures is suggested - a high prevalence in breeder pigs needs to be addressed first, followed by control of feed and then control of environmental contamination. Also according to the QMRA, for each MS, a reduction of two logs (99%) of Salmonella numbers on contaminated carcasses would result in a 60-80% reduction of the number of human salmonellosis cases attributable to pig meat consumption. The control of Salmonella in pig reservoir in the EU is a reasonable objective. The EU Salmonella control strategy in pigs should be continuously evaluated to identify possible improvements

Protein coding of neurodegenerative dementias: the neuropathological basis of biomarker diagnostics

Abstract: Neuropathological diagnosis of neurodegenerative dementias evolved by adapting the results of neuroanatomy, biochemistry, and cellular and molecular biology. Milestone findings of intra- and extracellular argyrophilic structures, visualizing protein deposition, initiated a protein-based classification. Widespread application of immunohistochemical and biochemical investigations revealed that (1) there are modifications of proteins intrinsic to disease (species that are phosphorylated, nitrated, oligomers, proteinase-resistant, with or without amyloid characteristics; cleavage products), (2) disease forms characterized by the accumulation of a single protein only are rather the exception than the rule, and (3) some modifications of proteins elude present neuropathological diagnostic procedures. In this review, we summarize how neuropathology, together with biochemistry, contributes to disease typing, by demonstrating a spectrum of disorders characterized by the deposition of various modifications of various proteins in various locations. Neuropathology may help to elucidate how brain pathologies alter the detectability of proteins in body fluids by upregulation of physiological forms or entrapment of different proteins. Modifications of at least the five most relevant proteins (amyloid-β, prion protein, tau, α-synuclein, and TDP-43), aided by analysis of further “attracted” proteins, are pivotal to be evaluated simultaneously with different methods. This should complement the detection of biomarkers associated with pathogenetic processes, and also neuroimaging and genetic analysis, in order to obtain a highly personalized diagnostic profile. Defining clusters of patients based on the patterns of protein deposition and immunohistochemically or biochemically detectable modifications of proteins (“codes”) may have higher prognostic predictive value, may be useful for monitoring therapy, and may open new avenues for research on pathogenesis.

Scientific Opinion on Fish Oil for Human Consumption. Food Hygiene, including Rancidity

Abstract: In this document an evaluation of hygiene and rancidity of fish oil intended for human consumption was carried out until the point of the production chain for fish oil at which a product intended for human consumption is obtained as a bulk stored product. This does not include encapsulated or other consumer packages or the final product ready to be sold to the consumer. Within the scope of this document, only oxidation products may represent a potential chemical hazard in refined fish oil intended for human consumption whilst stored in bulk. The refined fish oil production process typically includes several steps such as repeated heating at high temperatures (at 90-95°C and even up to 180°C) as well as alkali/acid treatments and removal of the water phase, which reduce the biological food safety risk to negligible. Lipid oxidation in bulk stored fish oil can be prevented by cold storage in darkness, without exposure to oxygen and addition of antioxidants. Based on the currently available information, no qualitative or quantitative risk assessment of hazards in relation to rancidity of fish oil intended for human consumption can be carried out. The criterion of 60 mg total volatile basic nitrogen (TVB-N)/100 g for whole fish is not based on scientific evidence. Sensory assessment is recommended for the evaluation of the freshness of raw material for fish oil production for human consumption. At present, the methods to determine the peroxide and anisidine values are the most reliable chemical methods for rancidity measurements in bulk fish oils. The present knowledge does not allow setting and recommending of maximum acceptable peroxide and anisidine values for the large variety of refined fish oils

Tubulin polymerization promoting protein (TPPP/p25) as a marker for oligodendroglial changes in multiple sclerosis

Abstract: Multiple sclerosis (MS) is an idiopathic chronic inflammatory demyelinating disease of the central nervous system with variable extent of remyelination. Remyelination originates from oligodendrocyte (OG) precursor cells, which migrate and differentiate into mature OG. Tubulin polymerization promoting protein (TPPP/p25) is located in mature OG and aggregates in oligodendroglial cytoplasmic inclusions in multiple system atrophy. We developed a novel monoclonal anti-TPPP/p25 antibody to quantify OG in different subtypes and disease stages of MS, and possible degenerative changes in OG. We evaluated autopsy material from 25 MS cases, including acute, primary progressive, secondary progressive, relapsing remitting MS, and five controls. Demyelinated lesions revealed loss of TPPP/p25-positive OG within the plaques. In remyelination, TPPP/p25 was first expressed in OG cytoplasms and later became positive in myelin sheaths. We observed increased numbers of TPPP/p25 immunoreactive OG in the normal appearing white matter (NAWM) in MS patients. In MS cases, the cytoplasmic area of TPPP/p25 immunoreactivity in the OG was higher in the periplaque area when compared with NAWM and the plaque, and TPPP/p25 immunoreactive OG cytoplasmic area inversely correlated with the disease duration. There was a lack of phospho-TDP-43, phospho-tau, α-synuclein, and ubiquitin immunoreactivity in OG with enlarged cytoplasm. Our data suggest impaired differentiation, migration, and activation capacity of OG in later disease stages of MS. Upregulation of TPPP/p25 in the periplaque white matter OG without evidence for inclusion body formation might reflect an activation state. Distinct and increased expression of TPPP/p25 in MS renders it a potential prognostic and diagnostic marker of MS.

Current concepts of neuropathological diagnostics in practice: neurodegenerative diseases.

Abstract: Definitive diagnosis of neurodegenerative diseases (NDDs) relies on the neuropathological evaluation. NDDs are defined as disorders with progressive loss of neurons showing distinct anatomical distribution, and accordingly different clinical phenotypes. Recent research has identified a spectrum of immunohistochemically detectable proteins deposited in the central nervous system which serve as a basis for protein-based disease classification. Accordingly, diagnostic criteria and disease staging have been updated. Furthermore, it has become evident that there is considerable overlap between deposited proteins and pathologies. This review summarizes recent achievements in neuropathological diagnosis and classification of NDDs and recommends approaches to be used during the diagnostic procedure in practice, thus to serve as guideline for a common level of diagnostic quality.

Scientific Opinion on the maintenance of the list of QPS (qualified presumption of safety) biological agents intentionally added to food and feed (2010 update)

Abstract: EFSA is requested to assess the safety of a broad range of biological agents (including microorganisms and viruses) in the context of notifications for market authorisation as sources of food and feed additives, enzymes and plant protection products The qualified presumption of safety (QPS) concept was developed by EFSA for its own use to provide a generic risk assessment approach applicable across EFSA’s scientific Panels, for biological agents notified for intentional use in the whole food chain The safety of unambiguously defined biological agents at the highest taxonomic unit that is appropriate for the purpose for which an application is intended are assessed, considering if the body of knowledge is sufficient Identified safety concerns for a taxonomic unit could be reflected as ‘qualifications’ when considered appropriate for an inclusion on the QPS list The list of QPS recommended biological agents is reviewed and updated annually The 2010 update reviews the previously assessed microorganisms including bacteria, yeasts, filamentous fungi and viruses used for plant protection purposes The recommendations of biological agents of the previous year were confirmed in the current update Qualifications relating to the agents recommended for QPS were reviewed, clarified and updated where necessary Specific sections dealing with antibiotic resistance relevant for QPS recommended microorganisms and yeast were included The methodology used for carrying out the annual review of the list of QPS recommended biological agents was detailed A list of microbial species from previous notifications and as notified to EFSA, annexed in this opinion, includes information on taxonomic units which are or are not recommended for the QPS list This list of notifications aims to summarize and maintain important information for future assessments and updates

Scientific Opinion on a quantitative estimate of the public health impact of setting a new target for the reduction of Salmonella in laying hens

Abstract: Public health risks of Salmonella infection in laying hens (Gallus gallus) can be associated with exposure through four different pathways: internally contaminated table eggs, externally contaminated table eggs, egg products and meat from spent hens. In relation to eggs, Salmonella Enteritidis is by far the serovar most frequently associated with human illness, and exposure through eggs that are internally contaminated with this serovar has a higher public health significance than exposure to externally contaminated eggs. A mathematical model, using reported field data from two EU Member States (MSs), suggests a linear relationship between the investigated scenarios of flock prevalence for Salmonella Enteritidis and the number of contaminated eggs that would be laid. However, the absolute public health impact of the assessed flock prevalence scenarios is highly uncertain due to lack of data on the number of contaminated eggs produced by infected flocks and on the true number of egg-related human salmonellosis cases. It is suggested that public health benefits, similar to those obtained reaching lower Salmonella flock prevalences, may be achieved by implementing controls based on more sensitive sampling protocols. Diversion of eggs from flocks that are tested positive in the EU Salmonella control programme to the production of egg products subjected to heat treatment may lead to increased health risks as heat treatment of egg products should not be considered an absolute barrier to Salmonella contamination. Fresh meat from spent laying hens might carry a higher prevalence of Salmonella than meat from broiler flocks, in particular if sourced from Salmonella-positive flocks. The quantification of under-ascertainment and underreporting of human salmonellosis cases, improving knowledge on within-flock dynamics of Salmonella and harvesting data on production of Salmonella contaminated eggs under field conditions would contribute to improving the accuracy of future quantitative estimates

Ultrastructural characteristics (or evaluation) of Creutzfeldt-Jakob disease and other human transmissible spongiform encephalopathies or prion diseases.

Abstract: The authors report on a large series of human prion diseases to establish ultrastructural characteristics that may be useful for their diagnosis. For Creutzfeldt-Jakob disease (CJD and its variant, vCJD) and fatal familial insomnia (FFI) only vacuolation (spongiform change) and the presence of tubulovesicular structures are consistent findings. Other changes, such as the presence of myelinated vacuoles, branching cisternae, neuroaxonal dystrophy, and autophagic vacuoles, were present in different proportions in either CJD or FFI, but they are nonspecific ultrastructural findings that can also occur in other neurodegenerative conditions. The hallmark of Gerstmann-Straussler-Scheinker disease (GSS) and vCJD is the amyloid plaque, but plaques of GSS and kuru are different than those of vCJD. Whereas the former are typical unicentric kuru type or multicentric plaques, the latter are unicentric florid plaques. Also, kuru plaques are nonneuritic, whereas GSS florid plaques are usually neuritic; however, a proportion of plaques from GSS was also found to have nonneuritic characteristics. Thus, the presence or absence of dystrophic neurites is not a discriminatory factor for GSS and vCJD. Furthermore, plaques from GSS with different mutations were also slightly different. In GSS with mutations P102L, 232T, and A117V plaques were stellate while in 1 case with 144 base-pair insertion and in GSS-A117V, round plaques were also observed, and typical primitive neuritic plaques, i.e., composed of dystrophic neurites with little or no amyloid, were found only in a P102L case from the original Austrian family. In 2 cases of sporadic CJD, the kuru stellate plaque predominated.

Scientific Opinion on BSE/TSE infectivity in small ruminant tissues

Abstract: The objectives addressed were i) to provide an update on TSE (Transmissible Spongiform Encephalopathy) infectivity distribution in small ruminant tissues; and ii) to indicate based on the current epidemiological situation as regards to BSE (Bovine Spongiform Encephalopathy) in the small ruminant population in the EU (European Union), whether a review of the existing SRM (Specified Risk Materials) list for small ruminants should be envisaged with regard to the potential exposure to the BSE agent. The appraisal was addressed by reviewing for Classical scrapie, BSE and Atypical scrapie in small ruminants aspects related to: i) tissue infectivity distribution according to the age and the genotype of sheep and goats; and ii) the infectious load in the different tissues. In order to perform the assessment all the currently available scientific results were reviewed, and data on TSE monitoring in small ruminants in the EU and on small ruminants slaughtered by species and age category in each EU Member State were considered. The reduction of the infectivity associated to the carcass of an infected individual achieved by the current SRM policy in small ruminants for Classical scrapie and BSE was estimated. The total number of Classical scrapie infected sheep and goats that could enter yearly into the food chain was provided. Moreover, considerations about Atypical scrapie were given. A set of simulations allowing estimating the impact of different policy options on the BSE infectious load potentially present in an infected sheep was provided

Cathepsin D (C224T) Polymorphism in Sporadic and Genetic Creutzfeldt-Jakob Disease

Abstract: Accumulation of cathepsin D immunoreactive lysosomes correlates with tissue pathology in sporadic Creutzfeldt-Jakob disease (CJD) brains. The C-to-T transition within exon 2 of the cathepsin D (CTSD) gene is associated with altered enzymatic activity. Possession of the TT genotype is a risk factor for variant CJD. To verify the association between the CTSD position 224T allele and the risk for and survival in sporadic and genetic CJD, we genotyped 540 sporadic, 101 genetic CJD, and 723 control individuals. Genotype data and duration of illness were compared using multiple logistic regression and Kruskal-Wallis test. Multivariate survival analysis was performed using Cox's regression model. The distribution of CTSD position 224 alleles was approximately the same in all groups. We observed a trend for shorter survival in sporadic CJD patients harboring the T allele at position 224 of the CTSD gene in particular in sporadic CJD patients with the prion protein gene position 129 MM genotype. We conclude that the CTSD position 224 polymorphism alone is not a significant risk or disease-modifying factor in sporadic or genetic CJD.

Peroxisomal Localization of the Proopiomelanocortin-Derived Peptides β-Lipotropin and β-Endorphin

Abstract: The peptide hormones ACTH, MSHs, β-lipotropin (β-LPH), and β-endorphin are all derived from the precursor molecule proopiomelanocortin (POMC). Using confocal laser microscopy and immunoelectron microscopy in human pituitary gland, we demonstrate a peroxisomal localization of β-endorphin and β-LPH in cells expressing the peroxisomal ATP-binding cassette-transporter adrenoleukodystrophy protein (ALDP). The peroxisomal localization of β-LPH and β-endorphin was not restricted to the pituitary gland but was additionally found in other human tissues that express high levels of ALDP, such as dorsal root ganglia, adrenal cortex, distal tubules of kidney, and skin. In contrast to the peptide hormones β-LPH and β-endorphin, which are derived from the C terminus of POMC, the N-terminal peptides ACTH, α-MSH, and γ-MSH were never detected in peroxisomes. This novel peroxisomal localization of β-endorphin and β-LPH in ALDP-positive cells was confirmed by costaining with ALDP and the peroxisomal marker catalase. Moreover, peroxisomal sorting of β-LPH could be modeled in HeLa cells by ectopic expression of a POMC variant, modified to allow cleavage and release of β-LPH within the secretory pathway. Although β-LPH and β-endorphin were only associated with peroxisomes in cells that normally express ALDP, the transporter activity of ALDP is not necessary for the peroxisomal localization, as demonstrated in tissues of X-linked adrenoleukodystrophy patients lacking functional ALDP. It remains to be elucidated whether and how the peroxisomal localization of POMC-derived hormones has a role in the endocrine dysfunction of peroxisomal disease.

EFSA Panel on Biological Hazards (BIOHAZ) Guidance on Revision of the joint AFC/BIOHAZ guidance document on the submission of data for the evaluation of the safety and efficacy of substances for the removal of microbial surface contamination of foods of animal origin intended for human consumption

Abstract: The BIOHAZ Panel of EFSA revised the joint AFC/BIOHAZ guidance on the submission of data for the evaluation of the efficacy of substances for the removal of microbial surface contamination of foods of animal origin. The guidance is intended to provide guidelines for dossiers of applications to be for authorisation of the substances mentioned above. This guidance requires data and information about the safety and efficacy of the substances, as well as examples of study designs at the laboratory and at the slaughterhouse in order to demonstrate these attributes. Also it includes the factors that should be considered when monitoring the safety and efficacy of a substance that has already been authorized and used. In addition all the factors related to the potential occurrence of acquired reduced susceptibility to biocides and/or resistance to therapeutic antimicrobials and the issues related to the environmental risk due to the use of such substances are considered in this guidance. The evaluation of these aspects is divided into pre-market and postmarket evaluation. In relation to the environmental risk, the guidance indicates the type of data and/or studies that an application should address on the impact of the disposal of the substances, with particular reference to the biological and chemical risk for the environment, the residues or their by-products in the carcasses and the potential development and dissemination of resistant strains

Scientific Opinion on a second update on the risk for human and animal health related to the revision of the BSE monitoring regime in some Member States

Abstract: The Bovine Spongiform Encephalopathy (BSE) monitoring system implemented in the European Union (EU) has been reviewed in this opinion for twenty five Member States (MSs). For this revision, MSs were divided into three groups depending on the number of years during which they have implemented the EU monitoring regime, and/or on the similarities of their epidemiological situations. Key assumptions made include: (i) full past compliance (for at least 6 years) with EU regulatory requirements for the surveillance and control of cattle BSE, (ii) future continuity of the BSE controls, and (iii) perfect sensitivity of the rapid tests employed for BSE surveillance. Two methodologies were applied to these three groups of MSs using available EU BSE monitoring data. The first one looks at the age of detected cases in each calendar year, while the second looks at the number of cases in successive annual birth cohorts. For the first group of MSs, these methodologies were applied in order to estimate the number of Classical BSE cases that would be missed under three different scenarios: (i) an increase in the age for BSE testing in cattle; (ii) stopping testing in cattle born after a certain date, and (iii) stopping testing of healthy slaughter cattle after certain dates. In the second group of MSs, the epidemiological situation was at least equivalent to that of the first group, and thus the conclusion was that they can be considered together for any potential revision of the BSE monitoring system. For the third group of MSs, it was not possible to calculate detailed estimates as their particular epidemiological situation compromises the application of some of the methods used. Recommendations are made in order to overcome the limitations encountered, and to ensure fitness of the EU monitoring regime for the purposes for which it is currently used

Scientific Opinion on the Neste Oil Application for a new alternative method of disposal or use of Animal By-Products

Abstract: EFSA’s Scientific Panel on Biological Hazards (BIOHAZ) was asked for a scientific opinion on a novel process developed by the Neste Oil Company as a safe means of disposal of animal by-products (ABP) according to Regulation (EC) 1774/2002. It is proposed that the method, known as the “Renewable Fuel” method, will be used for the treatment and disposal of Category 1 and Category 2 rendered animal fat obtained from animal byproducts that have been produced according to processing method 1 as referred to in Annex V, Chapter III of Commission Regulation (EC) 1774/2002 and for the treatment of Category 3 rendered animal fat that has been produced according to any of the processing methods 1 to 7 as referred to in the same Annex. The proposed process technology consists of a pre-treatment and of a continuous multiple step catalytic process. The main steps of interest for this assessment are called hydrodeoxygenation and isomerisation by the applicant. The production process can utilize a mixture of vegetable-oil and animal fat as feedstock. The Panel concluded that, in principle, the “Renewable Fuel” method may be appropriate for the safe destruction of BSE/TSE infectivity in animal waste. However, the company provided minimal data to support this conclusion (e.g. no quantitative estimate of the risk reduction level for Cat. 1 material was given). In the absence of such supporting data, the “Renewable Fuel” method cannot be considered safe for the treatment of such Category 1 wastes. The process proposed by Neste Oil can be considered to be safe for the treatment of Cat. 2 and 3 rendered animal fat since the input materials have already undergone a process ensuring adequate risk reduction

Immunologie und Infektionskrankheiten

Abstract: Die essenzielle Aminosure Tryptophan ist fur den Aufbau von Proteinen von zentraler Bedeutung. Daneben ist Tryptophan aber auch Substrat fur zwei wichtige biochemische Stoffwechselwege: (1) die Bildung des Neurotransmitters Serotonin (5-Hydroxytryptamin) durch das Enzym Tryptophan-5-Hydroxylase und (2) die Biosynthese von Kynureninderivaten und Nicotinamid-Adenin-Dinukleotiden, die durch die Enzyme Tryptophan-2,3-Dioxygenase (TDO, Tryptophanpyrrolase) und Indolamin-2,3-Dioxygenase (IDO) (EC 1.13.11.17) eingeleitet wird (Abb. 1) Open image in new window Abb. 1. Neben seiner Bedeutung als Proteinbaustein ist Tryptophan auch Substrat fur die Biosynthese des Neurotransmitters Serotonin (5-Hydroxytryptamin) durch das Enzym Tryptophan-5-Hydroxylase (T5H) und von Kynureninderivaten und Nicotinamid-Adenin-Dinukleotiden (NAD, NADH), die durch die Enzyme Tryptophan 2,3-Dioxygenase (TDO) und Indolamin 2,3-Dioxygenase (IDO) eingeleitet wird.