Search PubMed⌕ Search

Biomedical subjects

B Mansa

Publications and source records attributed to B Mansa.

At least 37 records · Page 2Linked to original sources
PubMed1986

Pathogenicity and persistence of pleural effusion disease virus isolates in rabbits.

Nine isolates of pleural effusion disease agent or virus (PEDV) from treponema-infected rabbits in various countries were examined for pathogenicity and persistence in rabbits. The isolates showed a wide range of pathogenicity and were categorized into three groups according to the severity of the acute infection. Group 1 comprised isolates causing more than 50% mortality, group 2 isolates causing mortality below 50%, while group 3 comprised isolates causing almost subclinical infections. The range between group 1 and group 3 was similar to that observed with virulent and avirulent progeny of the original PEDV isolate. Infection by each of the nine isolates resulted in a chronic low level viraemia which persisted for up to 2 years or more. Viral progeny of pathogenic isolates obtained in serum after the 2nd month of infection failed to induce clinical disease on rabbit inoculation. The chronic, subclinical infection was associated with a moderate, continued increase in serum IgG, but circulating immune complexes could not be demonstrated. Two years after infection slight histopathological changes were present in lymph nodes, spleen, liver, heart and lung. Evidence of immune complex disease could not be demonstrated.

Animals↗
PubMed1986

Retained antigen-binding activity of Fab alpha fragments of human monoclonal immunoglobulin A1 (IgA1) cleaved by IgA1 protease.

Immunoglobulin A1 (IgA1) proteases may be important virulence factors of certain bacteria involved in the pathogenesis of meningitis, gonorrhea, destructive periodontal diseases, and some other infections affecting mucosal membranes. This study evaluated the antigen-binding activity of free Fab alpha fragments released from human myeloma IgA1 by IgA1 protease from Haemophilus influenzae. Six myeloma proteins with antibody activity against streptolysin O, alpha-staphylolysin, or streptococcal hyaluronidase were used. Complete cleavage of the IgA1 myeloma proteins in the hinge region of the heavy chain did not affect their antigen-binding capacity. The titers of neutralizing activity associated with free Fab alpha fragments were not significantly different from those of the intact IgA1 proteins. The retained antigen-binding capacity of cleaved IgA1 is an important factor in the understanding of how IgA1 proteases may interfere with the immune protection of mucosal membranes.

Antibodies, Bacterial↗
PubMed1986

Characterization of intraepidermal IgG deposits in patients with primary Sjögren's syndrome.

In order to characterize the pathomechanisms behind intraepidermal in vivo deposits of IgG, which are found in 68% of patients with primary Sjögren's syndrome (primary SS), skin biopsies and serum from patients with epidermal IgG deposits were examined and compared to normal controls. Double-labelling experiments on skin biopsies, from 5 patients and 5 normal controls, showed that IgG deposits were predominantly located to surface membranes of OKT6 positive Langerhans cells. Only IgG1 and IgG3 were found deposited. Neither IgG2, IgG4, IgM, IgA, IgE, IgD, C1q, C3c, fibrinogen, albumin, beta-2 microglobulin nor C-reactive protein were found deposited in the epidermis of patients. Sera from 6 other patients with primary SS were examined for in vitro and in vivo binding of IgG to normal human epidermis. Using the athymic nude mouse/human skin model we were able to show that serum IgG from patients can be experimentally deposited in vivo in human skin transplants, but in vitro binding could not be demonstrated. The Fc-fragments of epidermal IgG were accessible to binding of anti-Fc-fragment antibodies and protein-A. We suggest that IgG-containing immune complexes constitute the intraepidermal IgG deposits seen in patients with primary SS, and that the binding possible is mediated by Fc-receptors of Langerhans cells and keratinocytes.

Fluorescent Antibody Technique↗
PubMed1984

A study of certain functional parameters of monocytes from patients with multiple myeloma: comparison with monocytes from healthy individuals.

Selected functions (i.e. phagocytosis and chemotaxis of circulating blood monocytes were studied on cells obtained from 20 patients with untreated multiple myeloma (MM) and the results were compared with those obtained on cells from 60 healthy persons. The mean number of circulating monocytes was only slightly increased over the normal value although a marked monocytosis was demonstrated in all of the 4 patients with M-components of the lambda light chain type. Plasma cells isolated from peripheral blood and from bone marrow of patients with MM were found to possess a strong alpha-naphthyl acetate esterase activity. No differences were observed in the phagocytic activity of monocytes from patients compared with those of the controls, whereas the chemotactic responsiveness of the monocytes from the patients was slightly increased.

Adult↗
PubMed1982

Antibodies to common viruses in sera from patients with multiple myeloma.

The results of screening for antibodies against rubella, morbilli, mumps, herpes simplex, rota and Epstein-Barr virus in serum from patients with multiple myeloma are reported. Antibodies against herpes simplex virus were found in all samples, present in high titres in most samples. Antibody titres against the other five viruses were generally low. A possible association of common virus infections and myelomatosis is discussed.

Aged↗
PubMed1982

Idiotypic and structural analysis of monoclonal human immunoglobulins with anti-streptolysin O activity.

The class, subclass and light chain distribution of eight myeloma proteins with anti-streptolysin O activity (ASO) in sera studied by our group and in cases from the literature indicates a predominance of the IgG1 kappa subclass and type of immunoglobulins. Three IgG myeloma proteins (O.I., L.F. and A.S.) were further characterized with respect to idiotypic cross-reaction and variable region subgroup. The anti-idiotypic antibodies (anti-Id) against protein O.I. and against protein L.F. both indicated idiotypic cross-reaction between O.I. and L.F. While in the case of anti-IdL.F. this cross-reaction was in the order of 5% it was much weaker when studied with anti-IdO.I.. The reaction between O.I. and anti-IdO.I. could be inhibited to 95% by the antigen streptolysin O, indicating that the idiotypic determinants are associated with the combining site. N-terminal amino acid sequence analysis showed that all three light chains fall in the V kappa III variable region subgroup. The heavy chains of proteins O.I. and L.F. with idiotypic similarities both have blocked N-termini, indicating the presence of the VHI or VHII subgroup while protein A.S. belongs to the VHIII subgroup.

Amino Acid Sequence↗
PubMed1981

Pleural effusion disease in rabbits. Observations on viraemia, immunity and transmissibility.

Baby rabbits surviving infection with pleural effusion disease virus (PEDV) developed viraemia persisting for at least six months. Only the infectious serum samples collected during the first 2 months of disease could transfer the typical PED. Six months after neonatal infection, virus concentration in serum was 102 to 104 rabbit-infectious doses per ml, the level of IgG appeared elevated, and serum rendered non-infectious by ether-treatment had a protective effect in passive immunisation experiments. No evidence of glomerulonephritis or deposits of immunoglobulins could be demonstrated in the kidneys. During the nursing period PEDV was transmitted from infected baby rabbits to two out of four dams, but not to control litter-mates. After the nursing period control rabbits, caged together with the viraemic rabbits for 60 to 150 days, remained free from PEDV infection.

Animals↗
PubMed1980

The ultrastructure of bone marrow plasma cells obtained from patients with multiple myeloma during the clinical course of the disease.

The ultrastructure of plasma cells from 65 consecutive bone marrow specimens from 13 patients with multiple myeloma is described. Biopsies were taken from 12 of the patients prior to and after initiation of treatment. The study was undertaken with the aim of correlating ultrastructural characteristics of the myeloma cells with biochemical and clinical parameters, including the survival time after treatment of the patients with cytostatics. Intranuclear inclusions were only seen in the cells of four patients, all of whom had rather long survival times. Two of these are still alive and, furthermore, their plasma cells are characterized by a low mean number of mitochondria in each sectioned cell studied, i.e. 7 and 14, respectively. Nuclear bodies were found in about 7 per cent of the plasma cells in biopsies taken before treatment was initiated. During treatment this percentage increased significantly to about 16 (2P = 0.004). A nuclear/cytoplasmic asynchrony was a characteristic feature of the ultrastructure of the myeloma cells. During treatment a significant increase from 34 to 54 per cent (2P = 0.03) was observed in the number of plasma cells with slight asynchrony. No correlation could be established between any ultrastructural features and the values obtained with clinical tests considered of major prognostic significance at the time of diagnosis, e.g. the concentrations of serum creatinine, haemoglobin, serum albumin and serum calcium.

Adult↗
PubMed1980

An antigen common to a wide range of bacteria. I. The isolation of a 'common antigen' from Pseudomonas aeruginosa.

In crude water-soluble extracts of Pseudomonas aeruginosa 64 antigens can be demonstrated by crossed immunoelectrophoresis in agarose with polyvalent Pseudomonas-immunoglobulin. One of these antigens cross-reacts with antigens prepared from bacteria of a wide range of taxonomic groups. Monospecific immunoglobulins to this antigen (Common Antigen) were produced by immunization with the appropriate immunocomplex extracted from agarose. Common Antigen was purified by the combination of two fractionation methods: Precipitation of the crude extract with 18% (w/v) sodium sulfate, followed by gel filtration of the supernatant on a Sephadex G-200 column. By this method, 35% of Common Antigen from the crude extract was recovered, more than half of the fractions electrophoretically pure. Electrophoresis of reduced Common Antigen on a dodecyl sodium sulfate polyacrylamide gel revealed two protein bands with apparent molecular weights of 59-62 000 and 62-65 000, respectively. The untreated antigen, however, passed a column of Sephadex G-200 with the void volumen, indicating a substance of high molecular weight (> 4-600 000).

Antigens, Bacterial↗
PubMed1980

An antigen common to a wide range of bacteria. 2. A biochemical study of a "common antigen" from Pseudomonas aeruginosa.

Common Antigen (CA) of Pseudomonas aeruginosa has been shown to be a protein composed of polypeptide subunits of a molecular weight (MW) of about 62 000. The MW of this protein was estimated to 665 000 by gel filtration on sepharose CL-6B, to 800 000 by electrophoresis on polyacrylamide gradient gels and to about 900 000 by ultracentrifugation, on a sucrose gradient. By analytical ultracentrifugation with Schlieren optics a sedimentation coefficient (S20 degrees, W) of 22.65 was calculated. The isoelectrical point was determined to pH 4.4. The antigen was decomposed on exposure to proteolytic enzymes. Polysaccharide, lipid, deoxyribonucleic acid or ribonucleic acid were not demonstrated in CA. The amino acid content of CA was determined, and no hexosamine or abnormal residues were observed. The amino acid content of CA was determined, and no hexosamine or abnormal residues were observed. The antigen was degraded when heated to 100 degrees C for 4 min or when exposed to pH below 4 or above 11 at 4 degree C. CA has been isolated from the cytoplasmic water-soluble fraction of disintegrated bacteria and only trace-amounts could be obtained from envelope fractions after solubilization with Triton X-100.

Amino Acids↗
PubMed1980

Rubella IgM antibodies in sera from infants born after maternal rubella later than the 12th week of pregnancy.

The outcome of 338 pregnancies complicated by serologically confirmed rubella after the 12th week of gestation is reported. Therapeutic abortions were performed on 93 women, 1 pregnancy resulted in a spontaneous abortion and 5 in stillbirths. Cord blood or a sample collected at an age of 0--2 months from 209 liveborn infants were tested for rubella IgM antibodies after sucrose density gradient ultracentrifugation. Such antibodies were detected in samples from approximately 33% of infants born after maternal rubella in the 4th and 5th month of gestation, but only in 11% of infants born after maternal rubella later in pregnancy. The classical symptoms of congenital rubella were not observed with the possible exception of a suspected unilateral hearing loss in 1 infant born after maternal rubella in the 5th month of pregnancy.

Antibodies, Viral↗
PubMed1976

A study of Russell bodies in human monoclonal plasma cells by means of immunofluorescence and electron microscopy.

Five patients with a serum M component were shown to possess plasma cells containing Russell bodies. Four of the patients suffered from multiple myeloma, whereas the fifth probably had a different disease or was in a premyeloma stage. The Russell bodies stained blue with the May-Grünwald-Giemsa stain and were found both in the nuclei and in the cytoplasm of the plasma cells. Ultrastructural studies showed that the Russell bodies were osmophilic and those located in the cytoplasm were always situated within the cisternae of the rough endoplasmic reticulum. The intranuclear Russell bodies were always surrounded by a triple layered membrane, and some evidence was obtained that these bodies were first formed within the perinuclear space of the cells. Immunofluorescence studies using anti-L chain conjugates showed a positive marginate straining of the intranuclear as well as the cytoplasmic Russell bodies of the cells from all patients. Only one patient had cells with Russell bodies which also stained their location in the plasma cells. It is concluded that some plasma cells in multiple myeloma may produce an excessive amount of L chains which, in combination with a failure in the secretion of immunoglobulin molecules, may lead to the formation of Russell bodies.

Adult↗
PubMed1976

Streptococcal bacteriophage 12/12-borne hyaluronidase and its characterization as a lyase (EC 4.2.99.1) by means of streptococcal hyaluronic acid and purified bacteriophage suspensions.

Hyaluronic acid was obtained from filtrates of heat-killed cultures of Streptococcus pyogenes group A, strain K56, by simple ethanol precipitation and treatment with an adsorbent. The hyaluronic acid is pure as judged from chemical and sedimentation analyses. Particles of streptococcal bacteriophage 12/12 were isolated from phage-lysed group A streptococci by polyethylene glycol precipitation and isopyenic centrifugation. Electron micrographs of negatively stained preparations showed a typical Bradley group B virus with a long, flexible, cross-striated tail and a knob- or star-like structure at the distal tip of the tail. The hyaluronic acid is depolymerized upon incubation with the phage 12/12 virions. After extensive digestion, a mixture of at least four oligosaccharides is formed, the two smallest of which are a tetra- and octasaccharide terminating in reducing N-acetyl-D-glucosamine. The tetrasaccharide shows an absorption maximum at 231.5 nm with a molar extinction coefficient epsilon = 4820 litres X mole-1 X cm-1, and it is therefore concluded that the bacteriophage-borne hyaluronidase catalyses a beta-elimination. Accordingly it is classified as a hyaluronate lyase (EC 4.2.99.1).

Bacteriophages↗