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Biomedical subjects

J Jonsson

Publications and source records attributed to J Jonsson.

At least 73 records · Page 4Linked to original sources
PubMed1980

Some functional properties of the RNP nucleoplasmic antigen.

The effect of nuclear stimulators and inhibitors on the nuclear contents of nucleoplasmic antigens (ENA) was studied by the indirect immunofluorescence technique. Human autoimmune sera, one reacting with RNase-A-sensitive and one with RNase-A-resistant components of ENA in the passive haemagglutination test, were used as indicators of the RNP and Sm antigens, respectively. Phytohaemagglutinin and concanavalin A both caused an accumulation of these antigens in normal blood lymphocytes. With pokeweed mitogen, staphylococcal protein A, or purified protein derivative the accumulation was apparently restricted to B cells, alpha-amanitine, 10 microgram/ml, prevented the mitogen-induced accumulation of RNP in normal human blood lymphocytes and reduced the contents of this antigen in several lymphoblastoid cell lines and in HeLa cells but did not significantly affect the contents of Sm antigen in any of these cell types. The experimental results suggest that the RNP and Sm nucleoplasmic antigens are normal rapid-phase reactants integrated in physiological nuclear mechanisms rather than inert structural constituents of the nuclear matrix or the products of a latent virus.

Antigens↗
PubMed1978

Symptomatology and diagnosis in connective tissue disease. II. Evaluations and follow-up examinations in consequence of a speckled antinuclear immunofluorescence pattern.

Antibodies to soluble ribonucleoprotein (sRNP) are by definition a prerequisite for the diagnosis mixed connective tissue disease (MCTD). They are also found in 30--40% of other rheumatic conditions with a high titred speckled IFL reaction. The same is true for the most characteristic clinical features of MCTD, viz. Raynaud's syndrome and polymyositis--polymyalgia. The serological and clinical symptoms mentioned are closely associated. An association between anti-Sm and the SLE symptoms butterfly erythema, nephropathia, other visceropathias and cerebrovascular disease is confirmed by the present study. Although anti-Sm has less diagnostic specificity for SLE than has anti-ds-DNA, it is useful as a diagnostic aid in SLE cases lacking the latter antibody. The results of the present study tend to support the hypothesis that anti-sRNP may be associated with a prophylactive effect against serious vasculitis and nephropathia. When anti-sRNP and anti-Sm occur together they seem to act competitively so that the symptom associated with the antibody having the highest titre tends to dominate the clinical picture. Both anti-sRNP and anti-Sm produce speckled nuclear patterns in the indirect immunofluorescence test. Sera with immunofluorescence titres below 1/25 were not found to react against either sRNP or Sm. On the other hand all sera tested that had a speckled IFL reaction greater than or equal to 1/800 also had anti-sRNP.

Antibodies, Antinuclear↗
PubMed1977

On the aromatic hydroxylation of amphetamine in rat liver microsomes and perfused liver preparations: effects of long-term administration.

The liver microsomal p-hydroxylation of amphetamine to parahydroxyamphetamine (pOHA) was dependent on NADP and inhibited by carbon monoxide indicating the involvement of cytochrome P-450, SKF 525-A, fenfluramine and desmethylimipramine were the most effective inhibitors of this pathway of amphetamine metabolism. Repeated administraion of phenobarbital resulted in reduced p-hydroxylation of amphetamine in vitro. Chronic administration of amphetamine reduced the microsomal p-hydroxylation of amphetamine without apparent changes in the cytochrome P-450 levels or in the activity of NADPH-cytochrome c reductase. The aromatic hydroxylation of aniline and the demethylation of ethylmorphine was not affected by this treatment. However, the 455 nm complex formed during the microsomal metabolism of N-hydroxy-amphetamine was increased by the long-term administration of amphetamine. These results indicate some pecularities of the in vitro hydroxylation of amphetamine by rat liver microsomes. Amphetamine disappeared from the perfusate of the perfused liver at the same rate in rats given a single dose of amphetamine and in rats given amphetamine orally for four weeks. The excretion of pOHA and its conjugate increased at 60 and 90 min. and 30, 60 and 90 min. respectively in the perfusate of the same experiment as compared to the controls. The total excretion of radioactive amphetamine metabolites at the end of the perfusion was increased in the perfusate and reduced in the bile compared to the control experiment.

Administration, Oral↗
PubMed1977

Metabolism of 2-nitro-1-phenylpropane to phenylacetone by rabbit liver microsomes.

Phenylacetone was found to be the major metabolite formed when 2-nitro-1-phenylpropane was incubated with rabbit liver microsomes. The enzymatic character of the reaction was demonstrated by the increase of product with microsomal protein and dependency on NADPH and oxygen. Furthermore, phenobarbital induction markedly increased the formation of phenylacetone. Carbon monoxide decreased the reaction indicating the involvement of a metalloenzyme. Experiments with H218O indicated that the carbonyl oxygen originated from water. It is suggested that the microsomal metabolism of 2-nitro-1-phenylpropane involves an enzymatic step followed by chemical hydrolysis of an intermediate, possibly a secondary nitronic acid.

Acetone↗
PubMed1977

Identification of metahydroxyamphetamine as a metabolite of amphetamine in the rat.

m-Hydroxyamphetamine (mOHA) was found as a metabolite of amphetamine in rat urine, liver perfusate and bile. The identity was established with a gas chromatograph-mass spectrometer (GC/MS) by its retention time, mass spectrum and selective-ion-monitoring of fragments representing both the side chain and the aromatic moiety. Furthermore, deuterium-labelled amphetamine was used in order to circumvent the possibility of interference by substances with similar structure of endogenous or exogenous origin. The amount of mOHA was low, about 10% of the ring hydroxylation could be accounted for as metahydroxylation.

Amphetamine↗
PubMed1976

Antibodies to synthetic ACTH in asthmatic and rheumatic patients.

The prevalence of antibodies against synthetic ACTH preparations and porcine gamma globulin was investigated in 29 asthmatic patients, in 28 rheumatic patients, and in 63 normal subjects of both sexes. Agglutinating antibodies were examined by a passive haemagglutination test and IgE antibodies by a radio-immuno assay. The incidence of agglutinating reactions against Synacthén and porcine gamma globulin was significantly higher in the asthmatic and rheumatic groups than in the group of normal subjects. Titres were generally low, attaining supposedly pathological levels (larger than or equal to 1/200) in about 10 per cent of the asthmatic patients and in 20-40 per cent of the rheumatic patients. In asthmatic patients, the incidence of ACTH specific IgE was higher than that in the normal group. This difference was not statistically significant in patients on routine treatment but it became satistically significant after ACTH booster treatment. In rheumatic patients the incidence of IgE antibodies against ACTH was insignificantly lower than that in the normal group. The incidence of agglutinating antibodies against vasopressin in asthmatic and rheumatic patients was also increased as compared with that in normal subjects and the titres were positively correlated to those against ACTH.

Adrenocorticotropic Hormone↗
PubMed1976

Antigenic properties of a DNA-preparation from calf thymus used for the demonstration of anti-DNA.

It was attempted to evaluate passive haemagglutination of antigen coated, tanned erythrocytes as a test by which to demonstrate anti-DNA in systemic lupus erythematosus. The antigens was prepared using a minimum of procedures in order to produce a native preparation. The resulting material had most of the criteria applying to native DNA, but the protein content was about 9%. It contained a thymocyte specific component, but no demonstrable trace of bovine species antigen. The reactions between the antigen and an anti-DNA serum from a patient with suspected SLE were inhibited by DNA and DNA-histone, but not appreciably by ENA, RNA or desoxyribonucleosides. Passive haemagglutination reactions against the antigen were positively correlated to a homogeneous immunofluorescence nuclear pattern and negatively correlated to a speckled pattern. Passive haemagglutination titres against ENA and DNA antigen were not correlated. Seventy-three per cent of randomly selected sera gave either purely DNase sensitive reactions (19%) or reactions of combined sensitivity to DNase and other enzymes. Twenty-eight out of 53 sera reacting in the passive haemagglutination test reacted also in the immunofluorescence test against Chrithidia luciliae kinetoplasts. The latter reactions were DNase sensitive. It applies to both tests that DNase sensitive, but RNase resistant, reactions were well correlated, irrespective of their sensitivity to trypsin while DNase resistant or DNase and RNase sensitive reactions were not correlated. The passive haemagglutination test using a native but relatively crude DNA-preparation coated on tanned sheep erythrocytes supplemented by specificity tests with DNase and RNase treated antigen gives about the same information as the indirect immunofluorescence test against Chrithidia luciliae kinetoplasts. Furthermore, the results show that patients' sera reacting with a homogeneous nuclear pattern in the indirect immunofluorescence test may contain not only anti-DNA and anti-nucleohistone antibodies, but also antibodies to a number of non-histone chromatin associated proteins some of which contain RNA.

Animals↗
PubMed1976

Effect of enzyme treatment of Chrithidia luciliae on the reactivity of its kinetoplast with anti-DNA sera.

The reactions of sera from patients with connective tissue disease with Chrithidia lucillae kinetoplasts were examined with the indirect immunofluorescence technique on untreated smears and smears pretreated with DNAse, RNAse or trypsin. Of 28 completely examined reacting sera, 20 had their reactions inactivated by DNAse alone, two by DNAse and trypsin, and 6 by DNAse and RNAse. This suggests that although the Chrithidia test is probably at present the method of choice for the diagnostic demonstration of DNA antibodies, its results are not completely unambigous. The kinetoplast DNA is probably conjugated to a non-histone protein and antibodies to the conjugate may occur in some instances. In other instances, antibodies may be directed against DNA-RNA complexes. If the Chrithidia kinetoplasts contain a protein moiety, the latter is apparently not identical with the protein contained in the Chrithidian cell nuclei.

Antibodies↗
PubMed1976

Symptomatology and diagnosis in connective tissue disease. Antibodies to extractable ribonucleoprotein in 123 patients reacting with cell nuclei in the immunofluorescence test.

Sera with an antinuclear immunofluorescence titre of 1/000 were taken consecutively from the diagnostic routine flow and examined for agglutinating antibodies against desoxyribonucleic acid (DNA) and extractable nuclear antigens (ENA). Passive haemagglutination tests with antigen-coated tanned erythrocytes were used and the specificity of the reactions was corroborated by testing against enzyme-treated cells. After the exclusion of the DNA-reacting 15%, three major groups and one minor could be distinguished on a serological basis. The largest group (41%) contained cases with a speckled immunofluorescence pattern and a RNase-trypsin sensitive agglutination reaction with ENA coated cells (sRNP). Nearly all cases of mixed connective tissue disease and scleroderma fell into this group which also contained 44% of the SLE cases. Symptomatically the group was characterized by remarkably high incidences of Raynaud's syndrome and myositis. The major group next in size comprised cases with a homogeneous immunofluorescence pattern but no reaction against DNA or ENA. Half of the cases within this group had the diagnosis SLE; they also constituted 42% of all SLE cases. The only other diagnosis of significant frequency within the group was unspecified collagenosis (23%). The symptomatology of the group was rather uncharacteristic, with the exception of the low incidence of Raynaud's syndrome. The third major group comprised cases with a speckled immunofluorescence pattern but no agglutination reaction against ENA or DNA. This group had a very high incidence of rheumatoid factor and also the highest incidence of visceral lesions among the groups. Yet the group contained only a small proportion (14%) of the SLE cases and the rheumatoid arthritis cases were about equally shared between this and the first group. The most common diagnosis in the group was unspecified collagenosis (40%). A fourth, small but homogeneous group contained cases with a speckled immunofluorescence pattern and a reaction with Sm antigen, i.e. an enzyme-resistant agglutination reaction with ENA. Six cases in this group had the diagnosis SLE. No diagnosis was available in two cases.

Antibodies, Antinuclear↗
PubMed1976

An extractable nuclear antigen not attaching to tannic acid-treated erythrocytes.

One of the antigens present in isotonic phosphate buffer extract of calf thymus nuclei against which antibodies are produced in collagen diseases, was shown not to attach to tanned sheep erythrocytes. It is, however, well exposed on slides coated with smears of ENA-extract and fixed with methanol-acetone. Reactions with the antigen can be demonstrated by the mixed haemadsorption technique. Preliminary results suggest that it may be a ribonucloprotein closely related to the 'soluble ribonucleoprotein" (sRNP) attachable to tanned erythrocytes. It may also have a similar relationship to clinical symptoms.

Animals↗
PubMed1975

Immune responses to treatment with natural and synthetic ACTH in bronchial asthma.

Two comparable groups of asthmatics each with 10 patients were treated during 2 years at scheduled intervals with either natural or synthetic ACTH up to a total dose of 2000-95-- IU. All patients had previously been given the natural but never the synthetic hormone. Intradermal tests with natural and synthetic ACTH were performed before treatment and after 1, 12 and 24 months. Serum samples were also taken on these occasions and analysed for antibodies against ACTH, vasopressin and porcine gamma-globulin. No sign of clinical allergy to ACTH was noted in any of the patients during the 2-year period. The incidence of intradermal reactions against natural ACTH was high at the onset of treatment but was not increased by treatment with either synthetic or natural ACTH, while the reactivity rate against synthetic ACTH was increased after both types of treatment. The incidence of IgE reactions against synthetic ACTH at the 20 U/ml level was significantly increased after 12 months' treatment with either natural or synthetic hormone. A high incidence of low-titered agglutinating antibodies against natural or synthetic ACTH was demonstrated before treatment in both the groups, but no significant change in incidence or mean titre against natural or synthetic ACTH or porcine gamma-globulin was noted during treatment with the natural or the synthetic preparation. A few patients, however, did display an increased agglutinating titre against ACTH after 12 months' treatment. Rather unexpectedly, most sera reacting with ACTH were found to react also with vasopressin and a significant increase of the incidence of these reactions and of the titres occurred during the treatment with synthetic as well as with natural ACTH. Two cases have been examined in detail, one because of a fulminant shock after synthetic ACTH and the other because of very high antibody titres without clinical symptoms of ACTH allergy.

Adrenocorticotropic Hormone↗
PubMed1975

The p-hydroxylation of amphetamine and phentermine by rat liver microsomes.

1. The products of p-hydroxylation of amphetamine and phentermine by two different preparations of rat liver microsomes were identified and quantitatively determined. At low concentrations (muM) significant proportions of the substrates were metabolized to the p-hydroxy derivatives by an NADPH-dependent system. The enzyme system was inhibited by higher substrate concentrations (mM) and was not induced by either phenobarbital or 3-methylcholanthrene. 2. The properties of this in vitro system are consistent with reports on in vivo studies of this reaction.

Amphetamine↗