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S Haavik

Publications and source records attributed to S Haavik.

At least 19 recordsLinked to original sources
PubMed2000

Glycosylation of immunoglobulin light chains associated with amyloidosis.

AL amyloidosis is a fatal disease caused by deposition of immunoglobulin light chains in a fibrillarforin (AL) in various organs. By searching the Kabat database of immunoglobulin sequences using the KabatMan software, we have shown that there is a preponderance of the consensus glycosylation sequon (AsnXxxSer/Thr) in the framework regions of amyloid light chains. We have characterised by computer graphics simulations, NMR spectroscopy and carbohydrate biochemistry the structure and conformation of the oligosaccharide from amyloid protein AL MS (lamba1) and from the amyloid associated Bence Jones protein of patient MH (kappa1). These proteins have glycosylation in the hypervariable complementarity-determining region versus framework region, respectively. Both contained a 2-6 sialylated core fucosylated biantennary chain mostly with bisecting GIcNAc. Together our results suggest that light chain glycosylation may be one of several modifications which may render the protein more prone to amyloid formation.

Amino Acid Sequence↗
PubMed2000

Building a demand-driven, vendor-managed supply chain.

Vendor-managed inventory (VMI) software can help both stand-alone and IDS-based hospitals significantly reduce supply-chain management costs. The software tracks an organization's actual supply demand and generates automatic purchase orders, providing the supplies on an as-needed basis. As a result, a hospital's inventory-carrying and purchase-order processing costs may be reduced significantly. To make optimum use of the VMI software, IDSs and hospitals first need to ensure that their methods of collecting data on supply consumption are efficient and accurate. They then need to either establish a relationship with a distributor offering VMI capability or, if the organization is a large IDS with its own distribution center, acquire the software for internal use. A collaboration with a distributor requires establishing effective electronic communications for data sharing.

Cost Control↗
PubMed1999

Specificity studies of an antibody developed against a mucin-type glycoprotein.

The specificity of a new anti-epiglycanin antibody (AE-3) which recognizes a mucin-type glycoprotein, the Human Carcinoma Antigen, found in the blood of patients with carcinomas, was studied. Information regarding the chemical nature of the antibody binding site was obtained by altering the structure of epiglycanin by chemical or enzymic means and testing the product in a competitive binding assay for inhibition of the binding of AE-3 to epiglycanin. The need for a high molecular weight antigen containing clustered T disaccharide, Gal,1-3GalNAc, was demonstrated. The specificity was further explored by inhibition studies with glycopeptides having one to three mono- to disaccharides. The results were interpreted using computer graphics molecular modeling which predicted the specific recognition of hydroxyl groups on oligosaccharides on adjacent amino acids. Thus T antigen O-linked glycopeptide tumour markers can be designed to be distinguished by antibodies by the amount of clustering of their oligosaccharides.

Amino Acid Sequence↗
PubMed1998

Human carcinoma-associated antigen (HCA), isolated from the endometrial carcinoma cell line KLE-1 and ascitic fluid of a patient with ovarian carcinoma; comparison with epiglycanin.

Human carcinoma-associated antigen (HCA), detected by the mouse monoclonal anti-epiglycanin antibody, AE-3, has been isolated from ascitic fluid taken from a patient with metastatic ovarian adenocarcinoma and from spent medium of the human endometrial carcinoma cell line KLE-1 and compared with epiglycanin. The ascitic fluid and the spent medium were concentrated by a Filtron Ultrasette 100 K Omega membrane and fractionated by gel filtration on Sepharose CL-2B. The active fractions which consisted mainly of glycoproteins having relative molecular weights in the range 1000-2000 kDa compared to dextrans, were further purified by affinity chromatography on a column of immobilized AE-3. The active fraction was subjected to SDS-PAGE and blotted onto a PVDF membrane. The amino acid composition of HCA isolated from the two sources, were related but not identical and both showed some differences from the amino acid composition of epiglycanin. They all have, however, compositions typical of mucin-type glycoproteins. The isoelectric point for HCA from both KLE-1 and ascitic fluid were determined to be at pH 1.8 and the buoyant densities were about 1.4 g/ml as determined by cesium trifluoroacetate gradient centrifugation.

Aged↗
PubMed1992

Development and characterization of monoclonal antibodies against a mucin-type glycoprotein.

The preparation of greater than 30 different hybridomas, all secreting IgM class antibodies against epiglycanin, a glycoprotein at the surface of the mouse mammary carcinoma cell line TA3-Ha, is described. The specificities of 10 of the antibodies, with affinity constants in the range of 10(8)-10(10) l/mol were compared in an enzyme competitive binding assay. The affinity of epiglycanin was strongly reduced for all antibodies tested by incubation with periodate (10 mM, 4 degrees C) and was reduced for most of the antibodies by endo-alpha-N-acetyl- D-galactosaminidase. This suggested that carbohydrate, and specifically the Gal beta (1----3)GalNAc disaccharide, formed an integral part of the epitopes of most of the antibodies. The isolated disaccharide, however, exhibited 250,000 times less inhibitory activity in the competitive binding assay than epiglycanin. The binding capacity of epiglycanin was also reduced by incubation with trypsin or pronase, suggesting a high molecular weight dependency for binding. Incubation with sialidase increased its affinity for the antibodies. The binding of the antibodies to epiglycanin was strongly inhibited by peanut agglutinin, and to a lesser extent by lectins from Triticum vulgaris, Ricinus communis, Pisum sativum and Phaseolus vulgaris. None of the antibodies bound to any of eight different gangliosides immobilized on HPTLC plates. Mono- (Fab) and divalent [F(ab')2] fragments of the antibodies possessed very low affinity for epiglycanin. The results demonstrated that the specificities of the antibodies are related, but distinguishable, and they suggest that this epiglycanin-IgM model may be useful for studies on the general principles of the interaction between IgM antibodies and mucin-type glycoproteins.

Amino Acid Sequence↗
PubMed1987

Glycoprotein allergens in pollen of timothy. IV. Structural studies of a basic glycoprotein allergen.

Heat treatment of the glycoprotein allergen with alkaline tritiated borohydride released carbohydrate material in the molecular weight (MW) range 500-2,000 daltons. The radioactivity of the highest MW carbohydrate fraction was low, indicating the presence of alkali-stable hydroxyproline-arabinose linkages. N-acetylglucosaminitol containing 3H was detected in the hydrolysate of the low-MW carbohydrate, indicating that some of the carbohydrate is bound to the protein chain through a N-glycosidic linkage between N-acetylglucosamine and asparagine. The presence of this linkage was also suggested by fast atom bombardment mass spectrometry of pronase-digested allergen. The glycoprotein seems to contain only a few carbohydrate chains made up of a total of 25 monosaccharide units. Methylation analysis indicated that the carbohydrate moiety consists of galactopyranosyl units as branching points linked through 1,3,6-positions or as terminal galactopyranosyl residues, mannopyranosyl groups as part of the chain either as 1,3- or 1,4-linked units, and arabinofuranosyl groups as branching points linked through 1,3,5-positions or as part of the chain, either as 1,3- or 1,5-linked units or as terminal arabinofuranosyl residues.

Chemical Phenomena↗
PubMed1987

Glycoprotein allergens in pollen of timothy. V. Significance of the carbohydrate moiety for the immunological activity of a basic glycoprotein allergen.

When the allergen was oxidized with periodate the size of its precipitate in rocket immunoelectrophoresis (RIE) was reduced. Incubation of the allergen with various glycosidases did not significantly affect its precipitation in RIE. The binding of human IgE and IgG to allergen bound to nitrocellulose seemed not to be affected by incubation with alpha-L-fucosidase, beta-D-xylosidase, beta-D-galactosidase or periodate oxidation. Incubation with alpha-D-mannosidase reduced the binding of IgG to the allergen but not its binding of IgE. Periodate oxidation did not significantly affect the IgE binding of the allergen in radioallergosorbent test (RAST) inhibition. When RAST discs of the allergen were incubated with alpha-D-mannosidase, alpha-D-galactosidase, Arachis hypogaea lectin and concanavalin A, the IgE binding to the discs was slightly reduced. Pretreatment of the discs with the monoclonal antibody FMC-A9 against ryegrass pollen allergens and beta-D-xylosidase did not reduce their IgE binding. L-Arabinose, D-mannose, methyl-alpha-D-mannopyranoside, D-galactose, D-glucose or the monoclonal antibody FMC-A9 did not inhibit the binding of IgE to RAST discs of the allergen. After incubation of the allergen with pronase, it did not form a precipitate in RIE and its IgE-binding ability in RAST and RAST inhibition was almost completely lost.

Antigen-Antibody Reactions↗
PubMed1987

Glycoprotein allergens in pollen of timothy. III. Immunochemical and biological properties of a basic glycoprotein.

Crossed immunoelectrophoresis (CIE) and tandem CIE indicated that a basic glycoprotein allergen isolated from pollen of timothy is immunochemically identical to the allergen formerly denoted as antigen 30. The glycoprotein gave one band in SDS-PAGE and agarose isoelectric focusing. After transfer to nitrocellulose by electroblotting or by capillary blotting, the allergen specifically bound IgE from persons allergic to timothy pollen. The single allergen inhibited about 15% of the IgE binding to radioallergosorbent test discs of whole timothy pollen extract. Sera from patients investigated also contained detectable amounts of IgG towards the allergen. In quantitative skin prick tests, the mean activity of 2 micrograms/ml purified allergen in 7 patients was equivalent to that of a timothy pollen extract containing 10,000 BU/ml (assayed relatively to histamine in skin prick test). The ability of the allergen to form a precipitate in rocket immunoelectrophoresis was lost when it was heated to 80 degrees C or incubated with 4 M guanidine hydrochloride.

Allergens↗
PubMed1985

Purification of a basic glycoprotein allergen from pollen of timothy by high-performance liquid chromatography.

The use of high-performance ion-exchange and size-exclusion chromatography in the purification of the basic timothy pollen allergen antigen 30 (Ag 30) was investigated. The most efficient purification was achieved when an initial purification step on a CM-Sepharose CL-6B column was followed by chromatography on Mono S and TSK G 2000 SW columns. This procedure was highly reproducible and well suited for semi-preparative scale purification of the allergen. The purified allergen gave one band on isoelectric focusing, corresponding to a pI of 9.30. On fused rocket immunoelectrophoresis a single precipitate was obtained that coincided with the allergenic activity.

Allergens↗
PubMed1985

Glycoprotein allergens in pollen of timothy. II. Isolation and characterization of a basic glycoprotein allergen.

A basic glycoprotein allergen has been isolated from pollen of timothy by a combination of chromatography on columns of CM-Sepharose CL-6B, Bio-Gel P-30, DEAE-Sepharose CL-6B and Ultrogel AcA 44. The allergen which is immunologically identical with the allergen formerly denoted as antigen 30 had an isoelectric point of 9.45. The MW of the glycoprotein was found to be 54,000 and 38,000 by SDS-PAGE and gel filtration, respectively. The allergen contains arabinose (3.1%), fucose (0.7%), xylose (0.7%), mannose (2.1%), galactose (2.8%) and glucose (0.2%). In rocket radioimmunoelectrophoresis the allergen bound IgE from 57 (78%) of 73 patient sera tested. The allergen did not bind Yariv artificial galactosyl- and glucosyl-carbohydrate-binding antigens or a monoclonal antibody against ryegrass pollen glycoprotein allergens.

Allergens↗
PubMed1985

Glycoprotein allergens in pollen of timothy. I. Investigation of carbohydrates extracted from pollen of timothy (Phleum pratense) and purification of a carbohydrate-containing allergen by affinity chromatography on concanavalin A-sepharose.

On extraction of timothy pollen with aqueous buffer high molecular weight material (MW greater than 3,500) containing the sugars arabinose, fucose, xylose, mannose, galactose and glucose was rapidly released. When the allergen extract was subjected to crossed immunoaffinoelectrophoresis with lectins incorporated in the first- or second-dimension gel, some allergens were clearly retarded. A basic glycoprotein allergen, probably the one known as antigen 30, was bound to concanavalin A (Con A) and also to a lectin from Pisum sativum. This allergen was purified by a combination of Con A-Sepharose and CM-Sephadex chromatography, giving a product that contained the following sugars: arabinose (1.4%), fucose (traces), xylose (1.3%), mannose (2.0%), galactose (7.6%) and glucose (10.5%). The purified allergen appeared essentially homogeneous on isoelectric focusing and on gel permeation chromatography. The allergenic activity and acid phosphatase activity, which have been correlated by previous workers, were demonstrated to be entirely separable.

Allergens↗
PubMed1983

Modifying the self-injurious behavior of an infant with spina bifida and diminished pain sensitivity.

This clinical case study extends the literature on behavioral treatment of self-injury to an intellectually normal infant with spina bifida and diminished sensitivity to pain. After treatment by attention-play periods plus an aversive tasting substance applied to the injured finger, severe biting of the index finger was eliminated and the finger healed. Follow-up inquiries 2 months, 2 and 3 yr later revealed no biting and no substantial tissue damage.

Behavior Therapy↗
PubMed1979

Effects of the Feingold diet on seizures and hyperactivity: a single-subject analysis.

The effects of a dietary manipulation on seizure frequency and activity level of a 3 1/2-year-old male with tuberous sclerosis, mental retardation, and uncontrolled seizures were assessed. Using a reversal design, the Feingold (K-P) diet was presented and withdrawn three times, while the medication regimen remained unaltered. Every application of the K-P diet resulted in substantial reductions in seizure frequency. During a 21-week follow-up, seizure frequency remained low despite the phasing out of one drug, and seizures were reportedly eliminated 1 year later. Brief objective measures of hyperactivity failed to show any effect due to the diet changes.

Child, Preschool↗