H.J. Rozeboom, Tonje M. Bjerkan, Kor H. Kalk, Helga Ertesvåg, Synnøve Holtan, Finn L. Aachmann, Svein Valla, Bauke W. Dijkstra,
... S. Mørch Y.A. Borgogna M. Dentini M. Skjåk-Bræk G. Biomacromolecules. 2005; 6: 1031-1040Crossref PubMed ... Scopus (114) Google Scholar, 13Svanem B.I.G Skjåk-Bræk G. Ertesvåg H. Valla S. J. Bacteriol. ... makes longer G-blocks (13Svanem B.I.G Skjåk-Bræk G. Ertesvåg H. Valla S. J. Bacteriol. ... Josefsen K.D. Høidal H.K. Valla S. Skjåk-Bræk G. Levine D.W. Enzyme Microb. Technol. ... produces alternating MG sequences (16Høidal H. Ertesvåg H. Skjåk-Bræk G. Stokke B.T. Valla S. J. ... of the enzyme-substrate binding strength (17Sletmoen M. Skjåk-Bræk G. Stokke B.T. Biomacromolecules. 2004; 5: ...
Tópico(s): Enzyme Structure and Function
2008 - Elsevier BV | Journal of Biological Chemistry
Tonje M. Bjerkan, Carol L. Bender, Helga Ertesvåg, Finn Drabløs, Mohamed K. Fakhr, Lori A. Preston, Gudmund Skjåk‐Bræk, Svein Valla,
... H. Bakkevig K. Jain S. Suh S.J. Skjåk-Bræk G. Ellingsen T.E. Ohman D.E. ... our laboratory (19Ertesvåg H. Doseth B. Larsen B. Skjåk-Bræk G. Valla S. J. Bacteriol. 1994; 176: ... PubMed Scopus (118) Google Scholar, 21Svanem B.I. Skjåk-Bræk G. Ertesvåg H. Valla S. J. Bacteriol. ... 55) Google Scholar, 23Høidal H.K. Ertesvåg H. Skjåk-Bræk G. Stokke B.T. Valla S. J. ... Josefsen K.D. Høidal H.K. Valla S. Skjåk-Bræk G. Levine D. Enzyme Microb. Technol. 1999; ... T.M. Lillehov B.E. Strand W.I. Skjåk-Bræk G. Valla S. Ertesvåg H. Biochem. J. ...
Tópico(s): Polysaccharides and Plant Cell Walls
2004 - Elsevier BV | Journal of Biological Chemistry
Finn L. Aachmann, Britt I.G. Svanem, Peter Güntert, Steffen B. Petersen, Svein Valla, Reinhard Wimmer,
... S. Morch Y.A. Borgogna M. Dentini M. Skjåk-Bræk G. Biomacromolecules. 2005; 6: 1031-1040Crossref PubMed ... Scholar, 5Stokke B.T. Smidsrød O. Bruheim P. Skjåk-Bræk G. Macromolecules. 1991; 24: 6637-6645Google Scholar). ... H. Bakkevig K. Jain S. Suh S.J. Skjåk-Bræk G. Ellingsen T.E. Ohman D.E. ... R-modules (24Ertesvåg H. Doseth B. Larsen B. Skjåk-Bræk G. Valla S. J. Bacteriol. 1994; 176: ... calcium binding (24Ertesvåg H. Doseth B. Larsen B. Skjåk-Bræk G. Valla S. J. Bacteriol. 1994; 176: ... Drabløs F. Fakhr M.K. Preston L.A. Skjåk-Bræk G. Valla S. J. Biol. Chem. 2004; ...
Tópico(s): Glycosylation and Glycoproteins Research
2006 - Elsevier BV | Journal of Biological Chemistry
Sissel Hertzberg, Lise Kvittingen, T. Anthonsen, Gudmund Skjåk‐Bræk,
... Trondheim, NorwaySearch for more papers by this authorGUDMUND SKJÅK-BRÆK, GUDMUND SKJÅK-BRÆK Norwegian Biopolymer Laboratory Division of Biotechnology (NTH) ... Trondheim, NorwaySearch for more papers by this authorGUDMUND SKJÅK-BRÆK, GUDMUND SKJÅK-BRÆK Norwegian Biopolymer Laboratory Division of Biotechnology (NTH) ... tb18210.xCitations: 5 a S. Hertzberg and G. Skjåk-Bræk were supported by research funding from The ...
Tópico(s): 3D Printing in Biomedical Research
1990 - Wiley | Annals of the New York Academy of Sciences
... relationships relevant to biomedical and biotechnological applications Gudmund Skjåk-Bræk Gudmund Skjåk-Bræk 1NOBIPOL, Division of Biotechnology, University of Trondheim ... LinkedIn Cite Icon Cite Get Permissions Citation Gudmund Skjåk-Bræk; Alginates: biosyntheses and some structure-function relationships ...
Tópico(s): Enzyme Production and Characterization
1992 - Portland Press | Biochemical Society Transactions
... 17, (1971), 287– 296. 3 B. Larsen, G. Skjȧk-Braek, T. Painter, Carbohydr. Res., 146, (1986), 342– 345. 4 G. Skjȧk-Braek, B. Larsen, Carbohydr. Res., 139, (1985), 273– ... Chem. Scand., 21, (1967), 691– 704. 7 G. Skjȧk-Braek, B. Larsen, Carbohydr. Res., 103, (1982), 133– ...
Tópico(s): Polysaccharides and Plant Cell Walls
1987 - Wiley | FEBS Letters
Tracy Stockley, Patricia L. Chang,
... Scholar 28 Soon-Shiong, P., M. Otterlie, O. Skjak-Braek, O. Smidsrod, R. Heinta, R. P. Lanza & ... Feldman, R. Nelson, J. Komtebedde, O. Smidsrod, G. Skjak-Braek, T. Expevik, R. Heintz & M. Lee 1992. ... Yao, Z. Yao, T. Zheng, N. Merideth, G. Skjak-Braek, T. Expevik, O. Smidsrod & P. Sandford 1993. ...
Tópico(s): Renal Transplantation Outcomes and Treatments
1997 - Wiley | Annals of the New York Academy of Sciences
Ivan Donati, Ýrr Mørch, Berit L. Strand, Gudmund Skjåk‐Bræk, Sergio Paoletti,
... S.; Mørch, Y. A.; Borgogna, M.; Dentini, M.; Skjåk-Bræk, G. Biomacromolecules 2005, 6, 1031) and at ...
Tópico(s): Proteoglycans and glycosaminoglycans research
2009 - American Chemical Society | The Journal of Physical Chemistry B
Meirigeng Qi, Ýrr Mørch, Igor Lacı́k, Kjetil Formo, Enza Marchese, Yong Wang, Kirstie K. Danielson, Katie Kinzer, Shusen Wang, Barbara Barbaro, Gabriela Kolláriková, D. Chorvát, David Hunkeler, Gudmund Skjåk‐Bræk, José Oberholzer, Berit L. Strand,
... B, Kolláriková G, Chorvát D Jr, Hunkeler D, Skjåk‐Bræk G, Oberholzer J, Strand BL. Survival of ...
Tópico(s): Diabetes and associated disorders
2012 - Wiley | Xenotransplantation
... Google Scholar41. NESTRØGSTADØGRIM IKME: Kostholdsundersøkelser i Lom og Skjåk. Landsforeningen for kosthold og helse, Oslo, 1964. Google ...
Tópico(s): Lipoproteins and Cardiovascular Health
1965 - American College of Physicians | Annals of Internal Medicine
Gudmund Skjåk Bræk, Arne Jensen, Åge Mohus,
The combined effects of copper and zinc ions on the growth of three marine diatoms and one dinoflagellate in culture have been studied. The two metals were found to act synergistically to all algae except Phaeodactylum tricornutum Bohlin. With this species an antagonistic effect was observed. Addition of zinc ions reduced the inhibition of growth caused by the more toxic copper ions. Zinc toxicity to this alga increased at low concentration of magnesium, indicating a common route for divalent metal ...
Tópico(s): Environmental Toxicology and Ecotoxicology
1976 - Elsevier BV | Journal of Experimental Marine Biology and Ecology
Gudmund Skjåk Bræk, Dagfinn Malnes, Arne Jensen,
Tópico(s): Electrochemical sensors and biosensors
1980 - Elsevier BV | Journal of Experimental Marine Biology and Ecology
Gudmund Skjåk-Br˦k, Bjørn Lársen,
Tópico(s): Polysaccharides and Plant Cell Walls
1982 - Elsevier BV | Carbohydrate Research
Mentz Indergaard, Gudmund Skjåk‐Bræk, Arne Jensen,
Article Studies on the Influence of Nutrients on the Composition and Structure of Alginate in Laminaria saccharina (L.) Lamour. (Laminariales, Phaeophyceae) was published on January 1, 1990 in the journal Botanica Marina (volume 33, issue 3).
Tópico(s): Algal biology and biofuel production
1990 - De Gruyter | Botanica Marina
Olav Smidsrød, Gudmund Skjåk-Br˦k,
In recent years, entrapment of cells within spheres of Ca2+ alginate has become the most widely used technique for immobilizing living cells. This versatile method includes applications ranging from immobilization of living or dead cells in bioreactors, immobilization of plant protoplasts for micropropagation and immobilization of hybridoma cells for production of monoclonal antibodies, to entrapment of animal cells for implantation of artificial organs. This review evaluates the potential of this ...
Tópico(s): Pluripotent Stem Cells Research
1990 - Elsevier BV | Trends in biotechnology
David S. Feingold, Ronald Bentley,
... Chem. Soc., 108, (1986), 6773– 6778. 16 G. Skjåk-Bræk, B. Larsen, Carbohydrate Res., 139, (1985), 273– ...
Tópico(s): Glycosylation and Glycoproteins Research
1987 - Wiley | FEBS Letters
Gudmund Skjåk‐Bræk, Olav Smidsrød, B. Larsen,
High molecular weight alginates having a variety of initial composition and sequential structures were modified with a mannuronan-C-5 epimerase from Azotobacter vinelandii to yield polymers with a high content of guluronic acid and, hence, an enhanced ability to form gels with calcium ions. The monad, diad and triad frequencies in the modified polymers were determined by n.m.r. spectroscopy, and the strength of homogeneous gels prepared from them with calcium ions were measured and compared with ...
Tópico(s): Carbohydrate Chemistry and Synthesis
1986 - Elsevier BV | International Journal of Biological Macromolecules
Gudmund Skjåk‐Bræk, Hans Grasdalen, Olav Smidsrød,
Tópico(s): Hydrogels: synthesis, properties, applications
1989 - Elsevier BV | Carbohydrate Polymers
Anita Martinsen, Gudmund Skjåk‐Bræk, Olav Smidsrød,
Abstract Calcium alginate gel beads were prepared from a range of well characterized alginates. The physical properties of beads depended strongly on the composition, sequential structure, and molecular size of the polymers. Beads with the highest mechanical strength, lowest shrinkage, best stability towards monovalent cations, and highest porosity were made from alginate with a content of L ‐guluronic acid higher than 70% and an average length of the G‐blocks higher than 15. For these “high G” alginates ...
Tópico(s): Enzyme Catalysis and Immobilization
1989 - Wiley | Biotechnology and Bioengineering
Gudmund Skjåk‐Bræk, Erminio Murano, Sergio Paoletti,
Alginates, both commercial and laboratory made, are strongly fluorescent due to small amounts of polyphenolic materials. These contaminants can be detected by fluorescence spectroscopy in concentrations lower than 1 ppm. This technique has been used to measure polyphenols in a wide range of alginates and various procedures for preparation of biotechnological-grade alginates have been evaluated.
Tópico(s): Viral Infectious Diseases and Gene Expression in Insects
1989 - Wiley | Biotechnology and Bioengineering
Gudmund Skjåk‐Bræk, Sergio Paoletti, Teresa Gianferrara,
Treatment of non-aqueous spherical beads of calcium alginate, or alginic acid gel, with acetic anhydride in pyridine results in acetylation without degradation. The degree and pattern of substitution were investigated using n.m.r. spectroscopy and degradation with specific enzymes. At low degrees of acetylation, substitution occurred almost exclusively on the mannosyluronic acid residues. At high degrees of acetylation, only a minor proportion of the isolated guluronic acid residues was substituted. ...
Tópico(s): Proteoglycans and glycosaminoglycans research
1989 - Elsevier BV | Carbohydrate Research
Gudmund Skjåk‐Bræk, Flavio Zanetti, Sergio Paoletti,
Whereas acetylation does not severely affect the molecular weight and polydispersity index of alginate, it greatly enhances the swelling ability of calcium gels made from these polymers. The affinity of alginate for calcium ions is diminished by acetylation as shown by the effect on the c.d. spectra and by the decrease in gel strength. Viscosity data suggest that a modest degree of acetylation (d.a. up to ∼11%) causes an expansion of the molecular chain, whereas a higher d.a. generates more flexible ...
Tópico(s): Proteins in Food Systems
1989 - Elsevier BV | Carbohydrate Research
Kurt I. Draget, Sigrid Myhre, Gudmund Skjåk-Br˦k, Kjetill Østgaard,
A method for growing plant protoplasts immobilized in Ca-alginate is presented in detail. Two types of protoplasts, isolated from hypocotyls of Brassica napus cv. Niklas and leaf mesophyll tissue of Nicotiana sanderae cv. Crimson Bedder, have been used as examples to illustrate the general applicability of the method. The major advantage of the method is improved cellular protection during the first critical weeks after isolation. This is a protection both against mechanical strain and strong gradients ...
Tópico(s): Plant Genetic and Mutation Studies
1988 - Elsevier BV | Journal of Plant Physiology
Helga Ertesvåg, Svein Valla, Gudmund Skjåk‐Bræk,
Alginate is a linear 1-4-linked copolymer of β-d-mannuronic acid and its C-5-epimer α-l-guluronic acid. The polymer is produced by some algae and bacteria, and is used for numerous purposes in industry. Alginate is initially synthesized as mannuronan, which is then modified at the polymer level by mannuronan C-5-epimerases, alginate lyases, and O-acetylases. This generates a variety of heteropolymers where properties such as viscosity, chain stiffness, gel formation, water-binding potential, and ...
Tópico(s): Polysaccharides and Plant Cell Walls
2009 - Springer Nature | Microbiology monographs
Kåre A. Kristiansen, Bjørn Christian Schirmer, Finn L. Aachmann, Gudmund Skjåk‐Bræk, Kurt I. Draget, Bjørn E. Christensen,
The study of alginate hydrogels is of increasing interest, given their potential applications as biomaterials for tissue engineering and for encapsulating drugs and living cells. In this study, we present a new strategy for tailoring alginates on the basis of homopolymeric mannuronan, where the chain stiffness and the content of G-residues could be varied independently. Partial periodate oxidation (0–8%) followed by borohydride reduction, introducing flexible linkages through C2–C3 cleavage and ring ...
Tópico(s): Polysaccharides and Plant Cell Walls
2009 - Elsevier BV | Carbohydrate Polymers
Paul de Vos, Marek Bučko, Peter Gemeiner, Marian Navrátil, Juraj Švitel, Marijke M. Faas, Berit L. Strand, Gudmund Skjåk‐Bræk, Ýrr Mørch, Alica Vikartovská, Igor Lacı́k, Gabriela Kolláriková, Gorka Orive, Dennis Poncelet, José Luís Pedraz, Marion B. Ansorge‐Schumacher,
Bioencapsulation involves the envelopment of tissues or biological active substances in semipermeable membranes. Bioencapsulation has been shown to be efficacious in mimicking the cell's natural environment and thereby improves the efficiency of production of different metabolites and therapeutic agents. The field of application is broad. It is being applied in bioindustry and biomedicine. It is clinically applied for the treatment of a wide variety of endocrine diseases. During the past decades ...
Tópico(s): Microencapsulation and Drying Processes
2009 - Elsevier BV | Biomaterials
Størker T. Moe, Gudmund Skjåk‐Bræk, Olav Smidsrød,
The biopolymeric hydrogels are being employed as the promising carriers for delivery of numerous kinds of drug candidates. Hydrogel systems are capable of absorbing higher volume of aqueous fluid while keeping intactness of the structural features. These also provide an easy implementation of the targeted and controlled releasing of drugs to the specific organs. Their use can minimize the unfavorable side effects of conventional drug delivery. Alginate is an abundant natural polysaccharide that ...
Tópico(s): 3D Printing in Biomedical Research
1991 - Elsevier BV | Food Hydrocolloids
Anita Martinsen, Gudmund Skjåk‐Bræk, Olav Smidsrød, Flavio Zanetti, Sergio Paoletti,
The scope of the present work was to assess and compare different methods to determine molecular weight (MW) averages and molecular weight distributions (MWD) of two samples of sodium alginate of different composition. Weight average (Mw) and number average (Mn) molecular weights were determined by totally integrated laser light scattering (LLS), both at wide angles (WA) and at a low angle (LA), and membrane osmometry, respectively. The two alginates were fractionated by preparative and analytical size ...
Tópico(s): Viral Infectious Diseases and Gene Expression in Insects
1991 - Elsevier BV | Carbohydrate Polymers
Marit Otterlei, Kjetill Østgaard, Gudmund Skjåk‐Bræk, Olav Smidsrød, Patrick Soon‐Shiong, Terje Espevik,
Summary: Alginates are polysaccharides with gel-forming properties composed of 1,4-linked β-D-mannuronic acid (M), α-L-guluronic acid (G), and alternating (MG) blocks. Alginate can be used as a matrix for implanted cells in vivo. In this study, we have examined the ability of alginates and their components to stimulate human monocytes to produce tumor necrosis factor-a, interleukin-6, and interleukin-1. Alginates stimulated the monocytes to produce high levels of all three cytokines. Low G alginates ...
Tópico(s): Seaweed-derived Bioactive Compounds
1991 - Lippincott Williams & Wilkins | Journal of Immunotherapy
Patrick Soon‐Shiong, Edward C. Feldman, Richard L. Nelson, Jan Komtebedde, Olav Smidsrød, Gudmund Skjåk‐Bræk, Terje Espevik, R Heintz, Martin L. Lee,
Long-term euglycemia by intraperitoneal transplantation of microencapsulated islets has not been described in the diabetic large animal model. In this study, we report the successful long-term reversal of diabetes by this method in spontaneous diabetic dogs. We have identified fundamental mechanism (s) associated with alginate-based microcapsule fibrosis, and have devised methods to ameliorate this problem. These include the use of purified alginate of low mannuronic acid content and cytokine suppression. ...
Tópico(s): Diabetes and associated disorders
1992 - Wolters Kluwer | Transplantation