The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Yunhwa Peggy Hsieh - One of the best experts on this subject based on the ideXlab platform.
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immunoassay for the detection of animal Central Nervous Tissue in processed meat and feed products
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Juergen A Richt, Yunhwa Peggy HsiehAbstract:An indirect competitive enzyme-linked immunosorbent assay (icELISA) based on the detection of the thermal-stable Central Nervous Tissue (CNT) marker protein, myelin basic protein (MBP), was developed to detect animal CNT in processed meat and feedstuffs. Two meat samples (cooked at 100 °C for 30 min and autoclaved at 133 °C for 20 min) of bovine brain in beef and two feed samples (bovine brain meal in beef meal and in soybean meal) were prepared at levels of 0.0008, 0.0031, 0.0063, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8, and 1.6%. An anti-MBP monoclonal antibody (mAb3E3) was produced using the hybridoma technique and characterized using Western blot. The optimized icELISA was CNT-specific without cross-reactivity with either meat (beef and pork) or soybean meal samples and had low intra-assay (%CV ≤ 3.5) and interassay variability (%CV ≤ 3.3), with low detection limits for bovine MBP (6.4 ppb) and bovine CNT spiked in both meat (0.05%) and feed (0.0125%) samples. This assay is therefore suitable for the ...
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enhanced immunodetection of bovine Central Nervous Tissue using an improved extraction method
Food Control, 2014Co-Authors: Yunhwa Peggy HsiehAbstract:Abstract The infectivity of bovine spongiform encephalopathy (BSE) was mainly associated with bovine Central Nervous Tissue (CNT), which have been banned from food and feed chain in many countries. Detection of bovine CNT is important for the surveillance of BSE occurrence. Myelin basic protein (MBP) has been identified as a thermal-stable maker protein in CNT for the detection of CNT in processed meat and feedstuffs. This study reports an improved extraction method of MBP that substantially enhanced the detectability of bovine CNT. Two different buffers (10 mM phosphate buffered saline and 20 mM Tris) at neutral pH containing different salt concentrations (150 mM–1 M) were used to extract proteins from unheated and heated (100 °C for 30 min) bovine brain. The mixtures were extracted with different time periods (30–180 min) at room temperature. Results from indirect non-competitive enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot show that several factors (buffer type, salt valence and concentration, incubation time, and heat treatment) affected the MBP concentration in the extracts. The concentration of MBP increased with the increase of salt concentration in all extracts, but decreased with the increase of the incubation time in unheated samples. MBP was more effectively extracted with the buffers containing divalent salt (Ca2+ or Mg2+) than that of monovalent salt (Na+). The MBP concentration was higher in heated than unheated samples. The optimal method for MBP extraction was using 20 mM Tris–HCl containing 600 mM MgCl2 (pH 7.4) to extract heated (100 °C for 30 min) CNT samples for 1 h at room temperature. With this sample extraction method, the detection limit of an indirect competitive ELISA can be significantly improved from reported 10%–0.05% (g/g) of bovine brain Tissue.
Sabine Wenisch - One of the best experts on this subject based on the ideXlab platform.
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Glial Fibrillary Acidic Protein and Myelin Basic Protein as Markers for the Immunochemical Detection of Bovine Central Nervous Tissue in Heat-Treated Meat Products
Journal of Food Protection, 2005Co-Authors: Katja Herde, R Leiser, Martin Bergmann, C. Lang, Sabine WenischAbstract:Because bovine Central Nervous Tissue (CNT) is the main risk material in transmission of the infective agent of bovine spongiform encephalopathy, a suitable test is needed to enforce the ban on CNT in human foodstuffs in the United States and the European Union and to ensure that meat products are free of CNT. To detect bovine CNT in heat-treated meat products, we used immunohistochemistry and Western blots with antibodies against glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP). Both antigens were resistant to processing methods used for meat products. The anti-GFAP antibody showed a high degree of Tissue specificity, whereas the anti-MBP antibody had high species specificity, clearly differentiating between porcine and bovine CNT. Therefore, immunochemistry performed with both proteins provides an effective means for detecting bovine CNT in meat products.
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Procedures for the detection of unwanted ingredients in meat products with regard to BSE. 4. Histological and immunohistological procedures for the detection of Central Nervous system Tissue in meat products.
Fleischwirtschaft, 2000Co-Authors: Sabine Wenisch, Ernst Lucker, Erich Eigenbrodt, M Bulte, R LeiserAbstract:Suitable analytical methods are urgently needed with respect to assessment and control of human exposure risk to bovine spongiform encephalopathy. Among these, methods for the detection of specified risk material (SRM), especially of Tissues of the Central Nervous system (CNS), are currently of great interest. In this study we present an immunohistochemical procedure for the detection of Central Nervous Tissue in meat products. Cooked sausages with varying additions of bovine brain and a Bregenwurst containing 15% of porcine brain were produced to serve as reference material. Immunostaining with monoclonal antibodies against neuron specific enolase (γγ-enolase) specifically revealed the Central Nervous Tissue added. Within the positive reference material immunostaining was homogeneously distributed, whereas particles of connective Tissue and fragments of striated muscles revealed no signs of immunoreaction. Due to the present results immunohistochemical detection of Central Nervous Tissues by means of the glial fibrillary acidic protein as well as routine food histology must be regarded as inadequate methods. In general, however, routine histological methods might play a Central and basic role for the detection of non-neuronal SRM, especially of the lymphoreticular system.
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detection of Central Nervous Tissue in meat products an immunohistochemical approach
Nutrition Research, 1999Co-Authors: Sabine Wenisch, Ernst Lucker, Erich Eigenbrodt, R Leiser, M BulteAbstract:Abstract With regard to bovine spongiforme encephalopathy the consumers' loss of confidence in meat and meat products as well as the associated economic loss result from the lack of adequate methods for the detection of Central Nervous Tissue in meat and meat products within the scope of official food control. The present study has documented for the first time a highly specific immunohistochemical method for the detection of these unwanted ingredients in meat products. Cooked sausages with varying additions of bovine brain (0%, 7.4%, 13.3%) and a ‘Bregenwurst’ containing 15% of porcine brain were produced to serve as reference material. Immunostaining with monoclonal antibodies against neuron specific enolase (γγ - enolase) specifically revealed the Central Nervous Tissue added. Advantages of the immunohistochemical procedure are the low expenditure of time and cost, the low degree of methodological difficulty, and the high specificity of the immunoreaction. Beyond that, food histology as well as neurohistological staining techniques must be regarded as insufficient methods owing to the high degree of technology-induced destruction of the Central Nervous Tissue.
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development of an integrated procedure for the detection of Central Nervous Tissue in meat products using cholesterol and neuron specific enolase as markers
Journal of Food Protection, 1999Co-Authors: Ernst Lucker, Sabine Wenisch, Erich Eigenbrodt, R Leiser, K Failing, M BulteAbstract:The emergence of a new variant of Creutzfeldt-Jakob disease during the bovine spongiform encephalopathy epidemic has focused attention on the use of Tissue from the Central Nervous system (CNS) in food. So far, the banning of CNS Tissue could not be effectively controlled because procedures for detection were missing. With regard to preventive health protection and labeling law enforcement, we have developed an integrated procedure for the detection of CNS Tissue in meat products. Herein, we show that antigenic characteristics of neuron-specific enolase (NSE) quantitatively survive technological treatment including severe homogenization and pressure heating. Using both poly- and monoclonal antibodies against NSE in the Western blot, bovine and porcine brain could be detected in sausages, albeit with varying sensitivity (1 to 4%). Sensitivity was increased after reduction of fat content (30 to 40%) of the samples by means of a soxhlet extraction. This made possible the detection of brain addition as low as 0.25% when using monoclonal antibodies. Immunohistology showed distribution of CNS Tissue in heat-treated meat products to be homogeneous. Immunoreaction was not found to be bound to morphologically intact histological or cytological structures; however, it proved to be highly specific. The quantification of cholesterol provides a low-cost screening method for the rapid identification of meat products, suspicious with regard to CNS Tissue addition. Cholesterol content increased by 26 mg per 100 g of fresh substance for each percentage of brain added to internally produced reference material. Using three different approaches (internal reference material, raw material, and field samples), a provisional cutoff point of normal cholesterol content was calculated for emulsion-type cooked sausages to be 115 mg/100 g (P < 0.05).
Robert G Korneluk - One of the best experts on this subject based on the ideXlab platform.
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characterization of myotonic dystrophy kinase dmk protein in human and rodent muscle and Central Nervous Tissue
Human Molecular Genetics, 1995Co-Authors: Elisabeth J Whiting, James D Waring, Katsuyuki Tamai, Martin J Somerville, Maxwell Hincke, William A Staines, Johe Ikeda, Robert G KornelukAbstract:Myotonic dystrophy (DM) is the most common form of inherited neuromuscular disease in adults and is characterized by progressive muscle wasting and myotonia. The mutation responsible for DM has been identified as the amplification of a polymorphic (CTG) n repeat in the 3' untranslated region of a gene encoding a serine/threonine kinase (DMK). We have produced a polyclonal rabbit antibody preparation against a fusion protein encoding the C-terminal amino acids 471-629 of the human DMK gene. This antibody specifically detects products of both full length and truncated human DMK genes expressed in bacteria and in insect cells. On immunoblots, we observed protein species of -74 and 82 kDa in cardiac muscle, skeletal muscle, ependyma and choroid plexus. By immunofluorescence, DMK was found to localize post-synaptically at the neuromuscular junction of skeletal muscle, at intercalated discs of cardiac Tissue and at the apical membrane of the ependyma and choroid plexus. We have also detected two to three species (-45-50 kDa) in other regions of the brain. Synaptic localization of DMK in the cerebellum, hippocampus, midbrain and medulla was noted. These results suggest that DMK plays a specialized role in intercellular communication
R Leiser - One of the best experts on this subject based on the ideXlab platform.
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Glial Fibrillary Acidic Protein and Myelin Basic Protein as Markers for the Immunochemical Detection of Bovine Central Nervous Tissue in Heat-Treated Meat Products
Journal of Food Protection, 2005Co-Authors: Katja Herde, R Leiser, Martin Bergmann, C. Lang, Sabine WenischAbstract:Because bovine Central Nervous Tissue (CNT) is the main risk material in transmission of the infective agent of bovine spongiform encephalopathy, a suitable test is needed to enforce the ban on CNT in human foodstuffs in the United States and the European Union and to ensure that meat products are free of CNT. To detect bovine CNT in heat-treated meat products, we used immunohistochemistry and Western blots with antibodies against glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP). Both antigens were resistant to processing methods used for meat products. The anti-GFAP antibody showed a high degree of Tissue specificity, whereas the anti-MBP antibody had high species specificity, clearly differentiating between porcine and bovine CNT. Therefore, immunochemistry performed with both proteins provides an effective means for detecting bovine CNT in meat products.
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Procedures for the detection of unwanted ingredients in meat products with regard to BSE. 4. Histological and immunohistological procedures for the detection of Central Nervous system Tissue in meat products.
Fleischwirtschaft, 2000Co-Authors: Sabine Wenisch, Ernst Lucker, Erich Eigenbrodt, M Bulte, R LeiserAbstract:Suitable analytical methods are urgently needed with respect to assessment and control of human exposure risk to bovine spongiform encephalopathy. Among these, methods for the detection of specified risk material (SRM), especially of Tissues of the Central Nervous system (CNS), are currently of great interest. In this study we present an immunohistochemical procedure for the detection of Central Nervous Tissue in meat products. Cooked sausages with varying additions of bovine brain and a Bregenwurst containing 15% of porcine brain were produced to serve as reference material. Immunostaining with monoclonal antibodies against neuron specific enolase (γγ-enolase) specifically revealed the Central Nervous Tissue added. Within the positive reference material immunostaining was homogeneously distributed, whereas particles of connective Tissue and fragments of striated muscles revealed no signs of immunoreaction. Due to the present results immunohistochemical detection of Central Nervous Tissues by means of the glial fibrillary acidic protein as well as routine food histology must be regarded as inadequate methods. In general, however, routine histological methods might play a Central and basic role for the detection of non-neuronal SRM, especially of the lymphoreticular system.
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detection of Central Nervous Tissue in meat products an immunohistochemical approach
Nutrition Research, 1999Co-Authors: Sabine Wenisch, Ernst Lucker, Erich Eigenbrodt, R Leiser, M BulteAbstract:Abstract With regard to bovine spongiforme encephalopathy the consumers' loss of confidence in meat and meat products as well as the associated economic loss result from the lack of adequate methods for the detection of Central Nervous Tissue in meat and meat products within the scope of official food control. The present study has documented for the first time a highly specific immunohistochemical method for the detection of these unwanted ingredients in meat products. Cooked sausages with varying additions of bovine brain (0%, 7.4%, 13.3%) and a ‘Bregenwurst’ containing 15% of porcine brain were produced to serve as reference material. Immunostaining with monoclonal antibodies against neuron specific enolase (γγ - enolase) specifically revealed the Central Nervous Tissue added. Advantages of the immunohistochemical procedure are the low expenditure of time and cost, the low degree of methodological difficulty, and the high specificity of the immunoreaction. Beyond that, food histology as well as neurohistological staining techniques must be regarded as insufficient methods owing to the high degree of technology-induced destruction of the Central Nervous Tissue.
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development of an integrated procedure for the detection of Central Nervous Tissue in meat products using cholesterol and neuron specific enolase as markers
Journal of Food Protection, 1999Co-Authors: Ernst Lucker, Sabine Wenisch, Erich Eigenbrodt, R Leiser, K Failing, M BulteAbstract:The emergence of a new variant of Creutzfeldt-Jakob disease during the bovine spongiform encephalopathy epidemic has focused attention on the use of Tissue from the Central Nervous system (CNS) in food. So far, the banning of CNS Tissue could not be effectively controlled because procedures for detection were missing. With regard to preventive health protection and labeling law enforcement, we have developed an integrated procedure for the detection of CNS Tissue in meat products. Herein, we show that antigenic characteristics of neuron-specific enolase (NSE) quantitatively survive technological treatment including severe homogenization and pressure heating. Using both poly- and monoclonal antibodies against NSE in the Western blot, bovine and porcine brain could be detected in sausages, albeit with varying sensitivity (1 to 4%). Sensitivity was increased after reduction of fat content (30 to 40%) of the samples by means of a soxhlet extraction. This made possible the detection of brain addition as low as 0.25% when using monoclonal antibodies. Immunohistology showed distribution of CNS Tissue in heat-treated meat products to be homogeneous. Immunoreaction was not found to be bound to morphologically intact histological or cytological structures; however, it proved to be highly specific. The quantification of cholesterol provides a low-cost screening method for the rapid identification of meat products, suspicious with regard to CNS Tissue addition. Cholesterol content increased by 26 mg per 100 g of fresh substance for each percentage of brain added to internally produced reference material. Using three different approaches (internal reference material, raw material, and field samples), a provisional cutoff point of normal cholesterol content was calculated for emulsion-type cooked sausages to be 115 mg/100 g (P < 0.05).
Gyorgy Buzsaki - One of the best experts on this subject based on the ideXlab platform.
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four modified silver methods for thick sections of formaldehyde fixed mammalian Central Nervous Tissue dark neurons perikarya of all neurons microglial cells and capillaries
Journal of Neuroscience Methods, 1993Co-Authors: F Gallyas, Gyorgy BuzsakiAbstract:Four reliable silver methods for the visualization of acute or advanced phases of neuronal damage have been modified so that they can be performed with good results on materials freshly fixed with transcardial perfusion of buffered formaldehyde for other silver methods and immunocytochemical techniques. The four modified methods respectively stain: (1) the somata and dendrites of ‘dark’ (impaired) neurons, (2) the perikarya of all neurons, (3) microglial cells, and (4) capillaries. Without the present modifications the ‘dark’ neuron method is only effective with glutaraldehyde fixation while the other three methods predominantly stain myelin in freshly fixed mammalian Nervous Tissue.