The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Winfried Romer - One of the best experts on this subject based on the ideXlab platform.
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shiga toxins from cell biology to biomedical applications
Nature Reviews Microbiology, 2010Co-Authors: Ludger Johannes, Winfried RomerAbstract:Shiga toxin-producing Escherichia coli is an emergent pathogen that can induce haemolytic uraemic syndrome. The toxin has received considerable attention not only from microbiologists but also in the field of cell biology, where it has become a powerful tool to study intracellular trafficking. In this Review, we summarize the Shiga toxin family members and their structures, receptors, trafficking pathways and cellular targets. We discuss how Shiga toxin affects cells not only by inhibiting Protein Biosynthesis but also through the induction of signalling cascades that lead to apoptosis. Finally, we discuss how Shiga toxins might be exploited in cancer therapy and immunotherapy.
Alan J Grodzinsky - One of the best experts on this subject based on the ideXlab platform.
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tissue shear deformation stimulates proteoglycan and Protein Biosynthesis in bovine cartilage explants
Archives of Biochemistry and Biophysics, 2001Co-Authors: Eliot H Frank, Thomas M Quinn, Ernst B Hunziker, Alan J GrodzinskyAbstract:Abstract Chondrocytes are known to sense and respond to mechanical and physicochemical stimuli by multiple regulatory pathways, including upstream signaling, transcription, translation, posttranslational modifications, and vesicular transport. Due to the complexity of identifying the biophysical phenomena that occur during cartilage loading in vivo, the regulatory mechanisms that govern chondrocyte mechanotransduction are not fully understood. Recent studies have shown that fluid flow during dynamic compression of cartilage explants can stimulate proteoglycan and Protein synthesis. In this study, we examined the effect of deformations of cell and extracellular matrix on chondrocyte Biosynthesis. We used tissue shear loading, since tissue shear causes little volumetric deformation and can thereby decouple fluid flow from cell and matrix deformation. Shear loading was applied over a wide range of frequencies, 0.01–1.0 Hz, using 1–3% sinusoidal shear strain amplitudes, and the resulting proteoglycan and Protein syntheses were measured using radiolabel incorporation. In addition, quantitative autoradiography was used to investigate spatial variations in matrix Biosynthesis and to correlate these variations with the spatial profiles of biophysical stimuli. Our data show that tissue shear loading at 1–3% strain amplitude stimulated the synthesis of Protein by ∼50% and proteoglycans by ∼25% at frequencies between 0.01 and 1.0 Hz. The relatively uniform patterns of Biosynthesis in the radial and vertical directions within cylindrical explants revealed by autoradiography suggest that the stimulatory effect was associated with the relatively uniform deformation caused by simple shear loading. These results suggest that chondrocytes can respond to tissue shear stress-initiated pathways for the production of collagen and proteoglycan, which include deformation of cells and pericellular matrix, even in the absence of macroscopic tissue-level fluid flow.
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tissue shear deformation stimulates proteoglycan and Protein Biosynthesis in bovine cartilage explants
Archives of Biochemistry and Biophysics, 2001Co-Authors: Moonsoo M Jin, Eliot H Frank, Thomas M Quinn, Ernst B Hunziker, Alan J GrodzinskyAbstract:Chondrocytes are known to sense and respond to mechanical and physicochemical stimuli by multiple regulatory pathways, including upstream signaling, transcription, translation, posttranslational modifications, and vesicular transport. Due to the complexity of identifying the biophysical phenomena that occur during cartilage loading in vivo, the regulatory mechanisms that govern chondrocyte mechanotransduction are not fully understood. Recent studies have shown that fluid flow during dynamic compression of cartilage explants can stimulate proteoglycan and Protein synthesis. In this study, we examined the effect of deformations of cell and extracellular matrix on chondrocyte Biosynthesis. We used tissue shear loading, since tissue shear causes little volumetric deformation and can thereby decouple fluid flow from cell and matrix deformation. Shear loading was applied over a wide range of frequencies, 0.01-1.0 Hz, using 1-3% sinusoidal shear strain amplitudes, and the resulting proteoglycan and Protein syntheses were measured using radiolabel incorporation. In addition, quantitative autoradiography was used to investigate spatial variations in matrix Biosynthesis and to correlate these variations with the spatial profiles of biophysical stimuli. Our data show that tissue shear loading at 1-3% strain amplitude stimulated the synthesis of Protein by approximately 50% and proteoglycans by approximately 25% at frequencies between 0.01 and 1.0 Hz. The relatively uniform patterns of Biosynthesis in the radial and vertical directions within cylindrical explants revealed by autoradiography suggest that the stimulatory effect was associated with the relatively uniform deformation caused by simple shear loading. These results suggest that chondrocytes can respond to tissue shear stress-initiated pathways for the production of collagen and proteoglycan, which include deformation of cells and pericellular matrix, even in the absence of macroscopic tissue-level fluid flow.
Ludger Johannes - One of the best experts on this subject based on the ideXlab platform.
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shiga toxins from cell biology to biomedical applications
Nature Reviews Microbiology, 2010Co-Authors: Ludger Johannes, Winfried RomerAbstract:Shiga toxin-producing Escherichia coli is an emergent pathogen that can induce haemolytic uraemic syndrome. The toxin has received considerable attention not only from microbiologists but also in the field of cell biology, where it has become a powerful tool to study intracellular trafficking. In this Review, we summarize the Shiga toxin family members and their structures, receptors, trafficking pathways and cellular targets. We discuss how Shiga toxin affects cells not only by inhibiting Protein Biosynthesis but also through the induction of signalling cascades that lead to apoptosis. Finally, we discuss how Shiga toxins might be exploited in cancer therapy and immunotherapy.
Eliot H Frank - One of the best experts on this subject based on the ideXlab platform.
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tissue shear deformation stimulates proteoglycan and Protein Biosynthesis in bovine cartilage explants
Archives of Biochemistry and Biophysics, 2001Co-Authors: Eliot H Frank, Thomas M Quinn, Ernst B Hunziker, Alan J GrodzinskyAbstract:Abstract Chondrocytes are known to sense and respond to mechanical and physicochemical stimuli by multiple regulatory pathways, including upstream signaling, transcription, translation, posttranslational modifications, and vesicular transport. Due to the complexity of identifying the biophysical phenomena that occur during cartilage loading in vivo, the regulatory mechanisms that govern chondrocyte mechanotransduction are not fully understood. Recent studies have shown that fluid flow during dynamic compression of cartilage explants can stimulate proteoglycan and Protein synthesis. In this study, we examined the effect of deformations of cell and extracellular matrix on chondrocyte Biosynthesis. We used tissue shear loading, since tissue shear causes little volumetric deformation and can thereby decouple fluid flow from cell and matrix deformation. Shear loading was applied over a wide range of frequencies, 0.01–1.0 Hz, using 1–3% sinusoidal shear strain amplitudes, and the resulting proteoglycan and Protein syntheses were measured using radiolabel incorporation. In addition, quantitative autoradiography was used to investigate spatial variations in matrix Biosynthesis and to correlate these variations with the spatial profiles of biophysical stimuli. Our data show that tissue shear loading at 1–3% strain amplitude stimulated the synthesis of Protein by ∼50% and proteoglycans by ∼25% at frequencies between 0.01 and 1.0 Hz. The relatively uniform patterns of Biosynthesis in the radial and vertical directions within cylindrical explants revealed by autoradiography suggest that the stimulatory effect was associated with the relatively uniform deformation caused by simple shear loading. These results suggest that chondrocytes can respond to tissue shear stress-initiated pathways for the production of collagen and proteoglycan, which include deformation of cells and pericellular matrix, even in the absence of macroscopic tissue-level fluid flow.
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tissue shear deformation stimulates proteoglycan and Protein Biosynthesis in bovine cartilage explants
Archives of Biochemistry and Biophysics, 2001Co-Authors: Moonsoo M Jin, Eliot H Frank, Thomas M Quinn, Ernst B Hunziker, Alan J GrodzinskyAbstract:Chondrocytes are known to sense and respond to mechanical and physicochemical stimuli by multiple regulatory pathways, including upstream signaling, transcription, translation, posttranslational modifications, and vesicular transport. Due to the complexity of identifying the biophysical phenomena that occur during cartilage loading in vivo, the regulatory mechanisms that govern chondrocyte mechanotransduction are not fully understood. Recent studies have shown that fluid flow during dynamic compression of cartilage explants can stimulate proteoglycan and Protein synthesis. In this study, we examined the effect of deformations of cell and extracellular matrix on chondrocyte Biosynthesis. We used tissue shear loading, since tissue shear causes little volumetric deformation and can thereby decouple fluid flow from cell and matrix deformation. Shear loading was applied over a wide range of frequencies, 0.01-1.0 Hz, using 1-3% sinusoidal shear strain amplitudes, and the resulting proteoglycan and Protein syntheses were measured using radiolabel incorporation. In addition, quantitative autoradiography was used to investigate spatial variations in matrix Biosynthesis and to correlate these variations with the spatial profiles of biophysical stimuli. Our data show that tissue shear loading at 1-3% strain amplitude stimulated the synthesis of Protein by approximately 50% and proteoglycans by approximately 25% at frequencies between 0.01 and 1.0 Hz. The relatively uniform patterns of Biosynthesis in the radial and vertical directions within cylindrical explants revealed by autoradiography suggest that the stimulatory effect was associated with the relatively uniform deformation caused by simple shear loading. These results suggest that chondrocytes can respond to tissue shear stress-initiated pathways for the production of collagen and proteoglycan, which include deformation of cells and pericellular matrix, even in the absence of macroscopic tissue-level fluid flow.
John E Hesketh - One of the best experts on this subject based on the ideXlab platform.
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four selenoProteins Protein Biosynthesis and wnt signalling are particularly sensitive to limited selenium intake in mouse colon
Molecular Nutrition & Food Research, 2009Co-Authors: Anna P Kipp, Antje Banning, Evert M Van Schothorst, Catherine Meplan, Lutz Schomburg, Chris T Evelo, Susan L Coort, Stan Gaj, Jaap Keijer, John E HeskethAbstract:Selenium is an essential micronutrient. Its recommended daily allowance is not attained by a significant proportion of the population in many countries and its intake has been suggested to affect colorectal carcinogenesis. Therefore, microarrays were used to determine how both selenoProtein and global gene expression patterns in the mouse colon were affected by marginal selenium deficiency comparable to variations in human dietary intakes. Two groups of 12 mice each were fed a selenium-deficient (0.086 mg Se/kg) or a selenium-adequate (0.15 mg Se/kg) diet. After 6 wk, plasma selenium level, liver, and colon glutathione peroxidase (GPx) activity in the deficient group was 12, 34, and 50%, respectively, of that of the adequate group. Differential gene expression was analysed with mouse 44K whole genome microarrays. Pathway analysis by GenMAPP identified the Protein Biosynthesis pathway as most significantly affected, followed by inflammation, Delta-Notch and Wnt pathways. Selected gene expression changes were confirmed by quantitative real-time PCR. GPx1 and the selenoProteins W, H, and M, responded significantly to selenium intake making them candidates as biomarkers for selenium status. Thus, feeding a marginal selenium-deficient diet resulted in distinct changes in global gene expression in the mouse colon. Modulation of cancer-related pathways may contribute to the higher susceptibility to colon carcinogenesis in low selenium status.
