Biomedical subjects

B Nilsson

Publications and source records attributed to B Nilsson.

At least 19 recordsLinked to original sources

PubMed1992

Ganglioside binding proteins of calf brain with ubiquitin-like N-terminals.

Two ganglioside-associated protein components I and II have been isolated from crude ganglioside preparations of calf brain by DEAE-Sephadex ion-exchange chromatography. Both components exhibited binding capacity in aqueous media for gangliosides of the 'ganglio' series but not for neutral glycosphingolipids (polyglycosylceramides) and only a low capacity for sialosylparagloboside. Each protein bound individual gangliosides with different efficiency. Upon prolonged incubation of component I with gangliosides, complexes with high (30:1) and low (6:1) glycolipid/protein molar ratios were formed. The latter but not the former complex was able to penetrate Sephadex G-200 beads. Both components inhibited plating efficiency of cultured mouse N2a neuroblastoma cells. The molecular masses of components I and II were determined by SDS/PAGE to be 11-12 kDa and 28 kDa, respectively. Carbohydrates (fucose, mannose, galactose, N-acetylglucosamine, N-acetylgalactosamine, and some sialic acid) were found only in component II. When examined by reverse-phase HPLC each component separated into two major closely migrating peaks which were subsequently examined by Edman degradation. Amino acid sequences of the N-terminal portions of three of these peaks (one peak from component I and both peaks from component II) showed, as far as the sequences were established, identity with the sequence of ubiquitin. It is hypothesized that the proteins may be instrumental in intracellular trafficking of gangliosides.

Amino Acid Sequence↗

PubMed1992

Structural analysis of five new monosialylated oligosaccharides from human milk.

The total monosialylated oligosaccharide fraction from pooled human milk was isolated by gel filtration and ion-exchange chromatography. Further separation by HPLC using a mobile phase containing an ion-pairing reagent of triethylamine gave five new monosialylated oligosaccharides. Structural analysis was carried out by chemical analyses, fast atom bombardment mass spectrometry, and 500-MHz NMR spectroscopy. Combined structural data revealed the following new structures: [formula: see text]

Carbohydrate Conformation↗

PubMed1992

Structural characterization of x2 glycosphingolipid, its extended form, and its sialosyl derivatives: accumulation associated with the rare blood group p phenotype.

It has been suggested that the x2 glycosphingolipid (GSL) could offer a structural basis for a P-like antigen activity found in blood group p individuals [Kannagi R., Fukuda, M.N., Hakomori, S. (1982) J. Biol. Chem. 257, 4438]. The structures of the x2 and sialosyl-x2 GSLs have been confirmed unequivocally as shown below by +FAB-MS, methylation analysis by GC-MS, and 1H-NMR. We have established a [formula: see text] monoclonal antibody (TH2) specific for the GalNAc beta 1----3Gal beta 1----4GlcNAc epitope, the terminal trisaccharide of x2 GSL. Application of MAb TH2 on TLC immunoblotting together with chemical analysis indicates the following points of interest: (i) the existence of extended type GSLs having the same x2 terminal structure; (ii) the chemical quantities of x2, sialosyl-x2, and extended x2 found in blood cells and in various tissues including carcinomas being nearly the same; (iii) considerably larger quantities of x2 and x2-derived structures found in blood samples of rare blood group p individuals. The accumulation of x2 and its derivatives in blood cells of p individuals is in contrast to the occurrence of these GSLs as extreme minor components in normal human red blood cells and tissues, and they may be responsible for the reported P-like activity in blood group p individuals [Naiki, M., & Marcus, D. M. (1977) J. Immunol. 119, 537].

ABO Blood-Group System↗

PubMed1992

The prognostic significance of nuclear DNA content in prostatic carcinoma.

The prognostic significance of ploidy level was studied in prostatic carcinoma and compared with the prognostic significance of morphologic grade and clinical stage. A nonselected group of 145 patients was studied in whom prostatic carcinoma was diagnosed by fine-needle aspiration biopsy at the Karolinska Hospital in 1966. All patients had endocrine therapy and were observed for 23 years or until death. Ploidy level was determined from cytophotometric measurements of Feulgen-stained tumor cell nuclei. The original May-Grünwald-Giemsa-stained cytologic slides, on which the cancer diagnoses were based in 1966, were destained and subsequently Feulgen stained for cytophotometric analysis. From the Feulgen-DNA data, the tumors were classified as near-diploid, near-tetraploid, and highly aneuploid, variants D-type, T-type, and A-type, respectively. The A-type tumors progressed rapidly, and 96% of the patients with this type died of the tumor within 5 years and all patients with this type died within 7 years. D-type and T-type tumors progressed much more slowly. None of the patients with these types of tumors died of the tumor disease within the first 5 years after diagnosis. As many as 12% of the patients (crude survival rate; corresponding to a relative survival rate of 43%) were still alive 15 years after diagnosis. According to multivariate Cox regression analysis, ploidy compared with grade and tumor stage was the strongest predictor of survival.

Aged↗

PubMed1992

Conformational differences between surface-bound and fluid-phase complement-component-C3 fragments. Epitope mapping by cDNA expression.

In previous studies a subset of complement-component-C3 (C3) epitopes, C3(D), expressed in denatured and surface-bound C3 and C3 fragments, has been described. These epitopes were detected by antibodies raised against denatured C3. In the present study we used a cDNA expression strategy to localize epitopes recognized by monoclonal and polyclonal anti-C3(D) antibodies. First, DNAse I digestion of C3 cDNA was used to generate 200-300 bp fragments. These cDNA fragments were expressed as beta-galactosidase-C3 fusion proteins using the lambda gt11 vector. The fusion proteins were tested by Western-blot analysis for reactivity with monoclonal and polyclonal anti-C3 antibodies, and the location of the epitopes were determined by sequencing the cDNA fragments. Affinity-purified polyclonal anti-C3(D) antibodies specific for denatured C3 reacted strongly with the C3 fusion fragments corresponding to segments of the 40 kDa subunit of C3c (residues 1477-1510) and the C3d fragment (residues 1117-1155 and 1234-1294) of C3. Adsorption of the polyclonal antibodies with a mixture of EAC3b and EAC3bi (degradation fragments of C3 bound to sheep erythrocytes) abolished binding to fusion proteins spanning the C3d region, but not the 40 kDa fragment of C3c. No effect was seen with the corresponding soluble C3 fragments. The monoclonal anti-C3(D) antibodies (mAbs) 7D326.1 and 7D331.1, specific for EAC3b and EAC3bi, bound to a fusion protein corresponding to amino acid residues 1312-1404, whereas mAb 7D9.2, specific for EAC3d, reacted with a fusion protein spanning amino acid residues 1082-1118. mAbs 4SD11.1 and 4SD18.1, which did not bind to any physiological C3 fragment, detected a fusion protein covering residues 1477-1510. In summary, the segments of C3 represented by amino acid residues 1082-1118, 1117-1155, 1234-1294 and 1312-1404 accommodate C3(D) epitopes that are expressed by erythrocyte-bound C3 fragments, but not by the corresponding fluid-phase fragment, whereas the segments spanning residues 973-1026 and 1477-1510 contain C3(D) epitopes that are exposed exclusively in denatured C3 and therefore hidden in physiological fragments of the protein.

Animals↗

PubMed1992

Disulfide exchange folding of insulin-like growth factor I.

The disulfide exchange folding properties of insulin-like growth factor I (IGF-I) have been analyzed in a redox buffer containing reduced (10 mM) and oxidized (1 mM) glutathione. Under these conditions, the 3 disulfide bridges of the 70 amino acid peptide were not quantitatively formed. Instead, five major forms of IGF-I were detected, and these components were concluded to be in equilibrium as their relative amounts were similar starting from either reduced, native, or a mismatched variant of IGF-I containing two non-native disulfides. The different components in the mixtures were trapped by thiol alkylation using vinylpyridine and subsequently isolated by reverse-phase HPLC. The purified variants were further characterized using plasma desorption mass spectrometry and peptide mapping. Two of the five different forms were identified as native and mismatched IGF-I. One form was a variant with only one disulfide bond, and the other two major components had two disulfides formed. In a separate experiment, early refolding intermediates were trapped by pyridylethylation after only 90 s of refolding in the glutathione buffer, starting from reduced IGF-I. The intermediates were identical to the components observed at equilibrium, but at different relative concentrations. On the basis of the disulfide bond patterns of the different components in the equilibrium mixtures, we conclude that the disulfide between cysteines-47 and -52 in IGF-I is an unfavorable high-energy bond that may exist in the native molecule in a strained configuration.

Alkylation↗

PubMed1992

Isolation of two novel sialyl-Lewis X-active oligosaccharides by high-performance liquid affinity chromatography using monoclonal antibody Onc-M26.

A monoclonal antibody, Onc-M26, that recognizes a cancer-associated antigen expressed by most human adenocarcinomas of the breast was shown previously to recognize a carbohydrate epitope carried on a hexaglycosyl ganglioside carrying the sialyl-Lewis X (SLex) antigen (P.S. Linsley et al., 1988, Cancer Res. 48, 2138-2148). Evidence that the antibody binds even more avidly to minor gangliosides containing more complex carbohydrate chains prompted us to search for a higher affinity epitope among sialylated oligosaccharides from pooled human milk. Affinity chromatography of a partially purified fraction of monosialylated milk oligosaccharides on a column containing monoclonal antibody Onc-M26 bound to a macroporous silica matrix gave a peak with a retention volume significantly greater than that of a standard SLex-active hexasaccharide. The retained material consisted of two nonasaccharides, each containing the SLex tetrasaccharide sequence, Neu5Ac alpha 2-3Gal beta 1-4(Fuc alpha 1-3) GlcNAc, linked beta 1-6 to a 3,6-disubstituted galactosyl residue.

Antibodies, Monoclonal↗

PubMed1992

Hereditary dysfunction of the third component of complement associated with a systemic lupus erythematosus-like syndrome and meningococcal meningitis.

OBJECTIVE: We describe a dysfunction of C3 in a patient with a systemic lupus erythematosus (SLE)-like syndrome. Alternative pathway complement function was absent, but classical pathway complement function was partially intact. METHODS: We used functional, preparative, and immunochemical techniques in the study. RESULTS: The patient's C3 proved normally susceptible to trypsin proteolysis and partially resistant to classical pathway, but completely resistant to alternative pathway, convertase-dependent cleavage. CONCLUSION: The dysfunction, thus, was caused by a failure of C3 to interact with the C3 convertases, rather than by a lack of a proteinase-sensitive cleavage site in the deficient protein.

Adult↗

PubMed1992

Serum IgA, IgG, and IgM responses to different enteroviruses as measured by a coxsackie B5-based indirect ELISA.

An enterovirus-specific indirect ELISA, based on a single local isolate of coxsackie B5 as antigen, was used to study the IgA, IgG, and IgM responses in 19 patients with a recent or current enterovirus infection. Twelve different enterovirus serotypes were isolated from 15 patients. Paired serum samples were available from 10 and a single serum from 5 of these 15 patients. In addition, 4 patients diagnosed by a significant titer rise of complement fixing antibodies to enterovirus were included. A serological diagnosis, defined as an increase in titer of enterovirus IgG and/or presence of enterovirus IgM, were established in all 14 patients with paired sera. Enterovirus IgM was present in either a single serum or in both sera in 13 of them. Out of 5 patients with a single serum sample only, enterovirus IgA or enterovirus IgM was found in 4. Specific IgA was present in either a single serum or in both sera in 14 of the 19 patients. Seven of the 10 enterovirus isolate patients with paired sera had a significant titer rise of complement fixing antibodies; however, all 10 were diagnosed by ELISA. Among 64 healthy controls 2 had enterovirus IgA and none had enterovirus IgM. In conclusion, the use of a single antigen-based ELISA was found to be reliable for the diagnosis of recent and current enterovirus infections.

Adolescent↗

PubMed1992

Expression of intestinal alkaline phosphatase in human organs.

Human intestinal alkaline phosphatase was immunohistochemically identified and localized in the pancreas, liver and kidney by use of a monoclonal antibody specific for intestinal alkaline phosphatase isozyme and by amplified biotin-streptavidin staining. In all the examined organs, the intestinal isozyme was found to be localized in the epithelial cells of ducts: bile ducts in the liver, distal convoluted tubules and collecting tubules in the kidney and ducts in the secretory epithelium in the pancreas. In the liver the antibody also stained some sinus-lining cells. In all the examined organs the endothelial cells of the capillaries and some vessels were stained. By use of immunoelectron microscopy, intestinal alkaline phosphatase was, as expected, found to be localized to the microvillar region of the small intestine. The isozyme was abundantly expressed in the apical area of the microvilli and in membrane remnants in the fuzzy coat. Capillaries and vessels in the submucosa were also stained, as well as small vesicles in the endothelial cells. The present investigation demonstrates the expression and localization of the intestinal alkaline phosphatase in several organs, though previously believed to be expressed only in the intestine.

Alkaline Phosphatase↗

PubMed1992

Blood transfusion in marrow graft recipients.

Of 182 consecutive patients undergoing allogeneic bone marrow transplantation (BMT), the relative numbers of those who received red blood cells (RBC), platelets (PLT), and granulocytes were 82%, 96%, and 26%, respectively. The transfused patients received an average of 1.26 (SD +/- 2.0) RBC units, 9.41 (SD +/- 13.2) PLT transfusions, and 0.33 (SD +/- 1.1) granulocyte concentrates per week per 50 kg body wt. in the period starting on the day of bone marrow transplantation (BMT) up to 60 days post BMT. The total number of units per transfused patient was 7.7 (range 1-63) RBC, 55.2 (range 2-394) PLT and 6.2 (range 1-36) granulocytes in the same period. Patients with grades II-IV acute graft-versus-host disease (GVHD) needed more RBC and PLT (p less than 0.001) than patients with grades 0-I acute GVHD. Patients with late engraftment required more granulocyte and PLT transfusion than those with early engraftment (p less than 0.05). Patients with high-risk malignancy had greater need for RBC and PLT than "low-risk patients" (p less than 0.02 and p less than 0.01), respectively). Patients with major ABO-incompatible donors showed a greater need for RBC than patients with minor ABO incompatibility (p = 0.02) or ABO identical donors (p = 0.01). Patients with relatively poor estimated survival required the most RBC and PLT.

ABO Blood-Group System↗

PubMed1992

Interval cancer and survival in a randomized breast cancer screening trial in Stockholm.

The aim of the present study was to analyse the survival rate in a group of breast cancers detected in the intervals between screening examinations in relation to clinically detected cancers in a non-screened population. All interval and control cancers were recruited from a randomized controlled mammography screening trial in Stockholm. The overall survival up to eight years of observation was higher in 191 patients with interval cancers than in 142 control cancers (p = 0.01). There were no significant differences between the two groups with regard to tumor size, stage distribution, or mean age, though the interval group did have a larger proportion of younger women. The similarity was confirmed by multiple regression analysis. The overall survival stage by stage was consistently higher in interval cancers. The survival rate in the true interval cancers was similar to that for those found in retrospect to have been detectable or traceable at the time of screening. No correlation was found between the length of the interval and the survival of patients with interval cancers. These results contradict the hypothesis that a high growth rate is associated with a poorer prognosis and that interval cancers are a more aggressive form of breast neoplasia.

Adult↗

PubMed1992

Mass spectrometry of high-mannose oligosaccharides after trifluoroacetolysis and periodate oxidation.

High-mannose oligosaccharides were treated with a mixture of trifluoroacetic acid and trifluoroacetic anhydride under conditions where reducing terminal N-acetylglucosamine residues are specifically degraded. The resulting mannose-containing products were, after further chemical modifications, analyzed by mass spectrometry in fast atom bombardment and electron ionization modes. Binding positions between monosaccharide residues were deduced from mass spectra of peracetylated compounds, which, prior to the derivatization, had been subjected to periodate oxidation and borodeuteride reduction.

Acetylation↗

PubMed1992

Fusions to the 5' end of a gene encoding a two-domain analogue of staphylococcal protein A.

A novel gene fusion system has been constructed for fusions to the 5' end of gene zz, encoding a two-domain analogue of staphylococcal protein A designated ZZ. Four different genes were fused to the 5' end of zz, and their gene products were analyzed. One of the genes encodes a protein located intracellularly in Escherichia coli and the other three genes encode gene products destined for secretion across the cytoplasmic membrane by the presence of an amino terminal signal sequence. After production in E. coli, the fusion proteins were purified in a single step by IgG-affinity chromatography. The purified ZZ fusions could be used directly for amino terminal sequencing to confirm the start of translation of the intracellular product and the processing of the signal peptide of the translocated products. This is the first example of ZZ fusions to the C-terminus of gene products. To simplify the general use of fusions to the 5' end of zz, a new plasmid vector was constructed containing a multi restriction enzyme cloning linker and the lacZ' gene which enables screening for production in alpha-complementing supE strains of E. coli on indicator plates.

Amino Acid Sequence↗

PubMed1992

Fusion proteins in biotechnology.

Gene fusion techniques allow the production of recombinant proteins featuring the combined characteristics of the parental products. Originally, these techniques were used to probe transcriptional and translational activity, to translocate proteins across cell membranes, and to facilitate the recovery of proteins. Recently, new applications have emerged in areas such as protein refolding, immunology, drug targeting and protein display. A slightly modified version of this review is also published in Current Opinion in Structural Biology 1992, 2:569-575.

Biotechnology↗

PubMed1992

Prognostic significance of mucosal aneuploidy in stage Ta/T1 grade 3 carcinoma of the bladder.

In a prospective series of 71 patients with newly detected grade 3, stages Ta and T1 bladder carcinoma tumor characteristics, including the results of deoxyribonucleic acid (DNA) analysis as well as morphological and DNA characteristics of the grossly normal urothelium, were investigated and related to progression-free survival. The mean duration of followup was 57 months, with a minimum of 24 months. Of the 71 patients 24 underwent primary cystectomy, and 47 were conservatively treated with transurethral resection alone, or followed by instillation therapy or irradiation therapy. Of the cystectomy and conservatively treated patients 2 (8%) and 16 (34%), respectively, died of bladder carcinoma. Among the 47 conservatively treated patients tumor progression could not be predicted by the initial characteristics of tumor stage, papillary or nonpapillary growth, tumor multiplicity, tumor size, existence of 1 or multiple aneuploid cell populations, S phase value, carcinoma in situ and atypia or aneuploidy in the mucosal biopsies. Neither was progression predicted by the recurrence rate during year 1 of observation. However, a change to or persistent mucosal aneuploidy and a change to or persistent morphological abnormality of the mucosa during year 1 of observation were predictive for tumor progression (p = 0.001 and 0.045, respectively). When compared in stepwise regression analysis (Cox's proportional hazard model), DNA aneuploidy in the mucosa at 12 months after diagnosis was a highly significant predictor, whereas morphology added no further prognostic information. Therefore, progression is related to gross chromosomal abnormalities of the mucosa. High risk patients can be identified by evaluation of the grossly normal mucosa, which should be done as part of the initial diagnosis and during followup in conservatively treated patients with stages Ta and T1, grade 3 bladder carcinoma.

Adult↗

PubMed1992

Stimulation of NK cell, T cell, and monocyte functions by the novel immunomodulator Linomide after autologous bone marrow transplantation. A pilot study in patients with acute myeloid leukemia.

Immunostimulatory therapy is at present considered after autologous bone marrow transplantation (ABMT) in order to mimic the allogeneic graft-versus-leukemia effect and thereby reduce the relapse rate. In a pilot study, five adults with acute myeloid leukemia were treated with the new immunomodulator Linomide post-ABMT. Linomide (0.3 mg/kg/week orally) was given in cycles of three weeks followed by three weeks of rest for up to six months. During treatment periods cyclic increases of CD56+CD3- and CD16+ NK cells were observed in parallel with enhanced cytotoxic activity of patient cells against both the NK-sensitive K562 and NK-resistant Daudi cell lines. A cyclic increase of CD14+ monocytic cells was also recorded. The proliferative responses of patient cells to PHA and allogeneic cells (MLC) were enhanced during Linomide therapy. The in vitro production of TNF alpha, IFN gamma, and IL-1 followed the same cyclic increase during treatment periods. Side effects were generally mild, and no harmful effects on engraftment were seen. Linomide therapy after ABMT thus induces a broad immunostimulation that offers a potential benefit with regard to leukemia-free survival.

Adjuvants, Immunologic↗

PubMed1992

Detection and characterization of immunoconglutinins in patients with systemic lupus erythematosus (SLE): serial analysis in relation to disease course.

The levels of IgA, IgG and IgM immunoconglutinins (IK) were assessed in sera from 20 patients with SLE which were followed for 8-month periods. At the time of the exacerbation, IgG IKs were significantly increased to 226 +/- 90 arbitrary units (mean +/- s.e.m.) compared with both the minimum value of 75 +/- 28 in the SLE patients and with 31 +/- 2 in healthy controls (P < 0.05). There was no difference between SLE patients and controls in the levels of IgM and IgA IKs. Most of the SLE patients in this material showed maximal IgG IK levels before exacerbation, but there was no correlation between the clinical disease index and the levels of IgG IK. The specificity of IgG IKs showed a broad diversity for microtitre-fixed C3b, iC3b, C3c and C3dg. The antibodies were of IgG1, IgG3 and in two patients, IgG4 subclass. IgG IKs were correlated to the C3d/C3 ratio which suggested that the IK responses were secondary to C3 activation. In summary, unlike other conditions associated with complement activation where elevated IgM IKs are common, an increase in IgG IK levels was observed. It is possible that this diverging IK response contributes to the pathophysiology of the disease.

Antibody Specificity↗