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Biomedical subjects

M Andersson

Publications and source records attributed to M Andersson.

At least 415 records · Page 23Linked to original sources
PubMed1988

Periodate-methylamine degradation of ribonucleotides in rat liver extracts in comparison to extracts of cultured cells.

Periodate-methylamine degradation of ribonucleotides, which enables separation of deoxyribonucleotides in cell extracts by high-performance liquid chromatography, was tested on the acid-soluble fraction of L1210 cells, Ehrlich ascites tumor (ELD) cells, liver tissue, and liver cell nuclei. It was shown that dTTP, dCTP, and dATP could be clearly separated in L1210 and ELD extracts. In samples from liver tissue, however, dTTP coeluted with another compound, the dCTP peak often eluted very close to another peak, and only dATP separated quite satisfactorily. Furthermore, extracts from liver cell nuclei, isolated in glycerol, were not directly susceptible to periodate oxidation. This problem can be avoided by use of a different procedure for the isolation of cell nuclei.

Animals↗
PubMed1988

Early increase in diadenosine tetraphosphate in regenerating rat liver.

Diadenosine tetraphosphate (Ap4A), a candidate for a signal molecule in the induction of DNA synthesis, was measured in regenerating livers of young adult rats at 12 and 24 h and of older rats at 24 h after partial hepatectomy. dATP and dTTP levels, which indicate the degree of proliferation in the livers, were determined by high-performance liquid chromatography and an enzymatic method, respectively. The Ap4A levels were increased in the beginning of DNA synthesis. In young rats the levels were about 140% of those of unoperated rats and in older rats about 300%. This increase was considerably smaller than that found in another study comprising two regenerating rat livers excised 20 h after partial hepatectomy, but still supports the hypothesis that Ap4A might take part in the onset of proliferation. The greater Ap4A increase in older rats may suggest a possible need for a stronger triggering mechanism to start proliferation in aged tissue. However, the experiments do not prove a function for Ap4A in the induction of DNA synthesis and it cannot be excluded that Ap4A is a product of an independent reaction.

Adenine Nucleotides↗
PubMed1988

Topical glucocorticosteroids and allergen-induced increase in nasal reactivity: relationship between treatment time and inhibitory effect.

The effect of topical glucocorticosteroids on the allergen-induced nasal hyperresponsiveness, with special reference to treatment time, was studied in a double-blind, randomized, placebo-controlled crossover study. Ten patients who previously had shown allergen-induced nasal hyperresponsiveness participated. After pretreatment with either placebo or various periods with topical glucocorticosteroids, they were subjected to an initial challenge with three increasing doses of allergen and were rechallenged after 24 hours with the lowest allergen dose from the previous day. The nasal responses were monitored by means of symptom scores and measurements of N alpha-p-tosyl-L-arginine methyl esterase (TAME) activity in nasal lavages. Five different treatment schedules were used. In the active treatment alternatives, the glucocorticosteroid treatment was started 48, 12 or 2 hours before or 2 hours after the initial allergen challenge. All treatments were continued up to rechallenge on the second day. As the active treatment we used budesonide, 100 micrograms in each nasal cavity every 12 hours. After placebo pretreatment, as expected, there was an increase in nasal symptoms at rechallenge as compared with the initial allergen challenge with the same allergen dose. The mean (+/- SEM) number of sneezes increased from 5.1 +/- 1.7 to 9.5 +/- 2.0 (p less than 0.05), a composite nasal symptoms score increased from 3.3 +/- 0.66 to 4.4 +/- 0.7 (NS), and TAME activity increased from 14.9 +/- 2.83 to 25.3 +/- 0.5 cpm.10(3) (p less than 0.05). Topical glucocorticosteroid treatment abolished this increase in nasal symptoms and TAME activity (p less than 0.05 for all treatment alternatives).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗
PubMed1988

Analgesic treatment in acute myocardial infarction. A double-blind comparison of ketobemidone + the spasmolytic A29 (Ketogan) and morphine.

The analgesic effect of ketobemidone hydrochloride + the spasmolytic component A29 (Ketogan) and morphine hydrochloride was compared double-blindly in patients with suspect acute myocardial infarction. The test drugs were administered i.v. in an initial dose of 0.5 ml (2.5 mg Ketogan, 5 mg morphine) followed, if necessary, by additional injections of 0.25 ml. Altogether, 309 patients participated in the trial. The total consumption of the test drugs showed that 5 mg Ketogan was equipotent with 10 mg of morphine. Treatment with Ketogan resulted in a significantly higher proportion of patients who were completely free of pain 15 and 30 min after the initial injection: 16% and 15% more, respectively, compared to morphine. Within 2 hours after the initial injection, approximately 15% of the patients in both treatment groups had reported nausea and about 7% had vomited (patients who vomited or were nauseated before treatment were not included in this analysis). The frequency of other side-effects was low, with no differences between the two treatment groups. Morphine caused a greater reduction of the systolic blood pressure than Ketogan. The effect of both drugs on pulse rate and respiration was the same.

Adult↗
PubMed1988

Allergen-induced hyperreactivity is not a feature of dermal immediate allergic reactions--in contrast to reactions of airways mucosa.

Allergen challenges of airway mucosa are commonly followed by an increased sensitivity to rechallenge with allergen. In the lower airways this phenomenon has been associated with the late phase of allergic airway reactions, which in turn has been suggested as a link between anaphylaxis and continuous allergic airway disease. The aim of the present investigation was to explore further the phenomenon of allergen-induced hyperreactivity and to see whether it was possible to induce such a reaction in the skin. Twenty-six patients with seasonal allergic rhinitis due to birch and/or grass pollens were studied in the pollen-free winter months. Nine of these patients had previously demonstrated an increased reactivity following allergen challenge in the nose, and nine of the patients had cutaneous allergen-induced late-phase reactions to the allergen tested. Skin-prick tests were performed with pollen allergen, histamine, and a negative control. The areas of the weal-and-flare reactions were measured 15 min after the tests were set. Any late-phase reactions were recorded 6 hr after the skin challenge. The subjects were re-tested with allergen and histamine 24 hr after the initial prick test within the area of the corresponding weal from the previous day. In contrast to previous challenges of human airway mucosa, where the same time interval was used, we found no increased responsiveness to rechallenge as compared with the initial allergen challenge. This was true, even if only the subgroups with previously demonstrated nasal allergen-induced hyperreactivity, or cutaneous late-phase reaction were evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Immediate and late phase allergic cutaneous reactions are not inducers of unspecific or specific local hyperreactivity.

The present study evaluates the possibility of allergen-induced unspecific and specific dermal hyperreactivity with special reference to the presence of late cutaneous reactions and allergen-induced nasal hyperreactivity. Twenty-six patients with strictly seasonal allergic rhinitis participated. All had a positive skin prick test for birch (Betula verrucosa) and/or timothy (Phleum pratense). Ten patients had previously displayed an allergen-induced nasal hyperreactivity and six patients a late cutaneous reaction. An initial skin prick test with a relevant pollen allergen was done in triplicate. The immediate skin reactions were recorded after 15 min and any late-phase reaction after 6 h. Twenty-four hours later the patients were retested. The same pollen allergen was sited in the first flare reaction from the previous day. A histamine prick test was sited in the weal as well as in the third reaction from day 1. A histamine control was also performed in a previously unaffected area. The allergen-induced weal reactions decreased significantly at rechallenge compared with the results from the previous day (P less than 0.05). The histamine tests resulted in similar skin reactions regardless of whether or not they were done on a previous allergen test site. This was true for both specific and unspecific reactions when the subgroups of patients with previously demonstrated allergen-induced nasal hyperreactivity or late-phase skin reactions were evaluated separately. These results indicate that allergen-induced hyperreactivity is not a general feature of allergic inflammation but is a phenomenon restricted to specific sites, such as the airway mucosa.

Adult↗
PubMed1988

Production and characterization of monoclonal antibodies directed against Bordetella pertussis lipopolysaccharide.

Hybrid cell lines producing monoclonal antibodies against Bordetella pertussis lipopolysaccharide (LPS) were established. The specificity of the antibodies was ascertained by enzyme-linked immunosorbent assay (ELISA) and ELISA-inhibition experiments with LPS and delipidated polysaccharide fragments (PS-1 and PS-2) prepared from B. pertussis LPS. Monoclonal antibody 9-1-H5 reacted with B. pertussis LPS only, whereas monoclonal antibodies 6-4-H6 and 9-2-A8 reacted with PS-1 and PS-2 as well as B. pertussis LPS. The antibodies did not react with LPS prepared from B. parapertussis and B. bronchiseptica in an LPS-specific ELISA. A monoclonal antibody-based sandwich ELISA was developed for detection of B. pertussis LPS. This assay had a detection limit of B. pertussis LPS in concentrations ranging from 0.16 to 0.32 microgram/ml. The assay was also shown to be specific for the detection of whole B. pertussis bacteria. No cross-reactions were observed with strains of Branhamella catarrhalis, Neisseria meningitidis, Streptococcus miteor, Haemophilus influenzae, or Legionella pneumophila. The monoclonal antibodies might be useful for the detection of soluble antigens and whole bacteria in clinical samples and for studies of the immunochemical structure of B. pertussis LPS.

Animals↗
PubMed1988

Violence in the family: morbidity and medical consumption.

Morbidity in homes, where family violence occurred, was investigated. Approximately 90% of the women and 60% of the men had been treated in hospital during a five-year period. Treatment in surgical department was most common. More women than men had symptoms indicating psychosomatic or indefinite aetiologies. One fifth of the women reported injuries due to physical violence. The medically certified illness for both men and women was about three times higher than in the general population. The children had twice as many admissions to hospital than controls. The diagnoses of the children were more frequently socially related. An early diagnosis of the family conditions and preventive measures are needed to safeguard against repeated battery and counteract social handicap.

Adult↗
PubMed1988

Laser welding of titanium in dentistry.

Unalloyed titanium of the quality used for osseointegrated implants by the method of Brånemark is also sometimes used for the metallic part of the prosthetic superstructure placed on the fixtures and for crowns and bridges of conventional type. Forty bars of titanium, 8 of ASTM B 348 grade-1 quality and 32 of ASTM B 348 grade-2 quality, were laser-welded, using dissimilar laser joint variables. Tensile strength, 0.2% proof stress, and percentage elongation of the welded bars were measured and compared with the corresponding values for the titanium bars as delivered and with those of brazed type-3 gold alloy bars of similar dimensions. The type of fracture was evaluated from fractographs. The results showed that the use of certain defined laser joint variables during welding produced values for the mechanical properties studied which were more favorable than those obtained from the brazed gold bars. The fracture of the titanium specimens was ductile, with dimples occurring at the fracture surfaces.

Dental Alloys↗
PubMed1988

Prednimustine, methotrexate, 5-fluorouracil, mitoxantrone and tamoxifen for advanced breast cancer in postmenopausal women. A phase II trial.

A phase II trial in postmenopausal women with advanced breast cancer naive to cytotoxic treatment for recurrent disease was performed with a combinated chemo-endocrine regimen of prednimustine, methotrexate, mitoxantrone, 5-fluorouracil, and tamoxifen. Thus we replaced the most toxic agents--cyclophosphamide and doxorubicin often used in combinations--with prednimustine and mitoxantrone respectively, which are supposed to be equally efficient but less toxic. Seventy-seven patients were registered but 6 were ineligible. Complete response was obtained in 11%, partial response in 29%, no change in 29%, and progressive disease in 31%. Median duration of response was 18.5 months, time to disease progression 9.2 months, and survival 16.0 months. Toxicity was modest; 61% had no or only moderate alopecia not necessitating a wig, 59% had no or only moderate, if any, nausea. Bone marrow suppression, especially thrombopenia, was a major dose limiting factor. This regimen seems to be effective and have low toxicity in advanced breast cancer in postmenopausal women.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Immunogenetics of type II collagen autoimmunity and susceptibility to collagen arthritis.

The MHC restriction of the antibody response and development of arthritis after immunization with autologous or heterologous type II collagens in mice have been investigated. Mice from three different H-2q-carrying strains (DBA/1, NFR/N and B10.G) with different non-MHC genes, as well as B10-congenic strains carrying wild type H-2q-related or H-2r haplotypes, were susceptible for collagen arthritis. All strains tested developed an antibody response cross-reacting with autologous type II collagen after immunization with heterologous type II collagen; H-2q predisposes for a high response against chick, rat and bovine type II collagen, H-2r and H-2b for a high response against bovine type II collagen. Only mouse strains with H-2q, H-2r, H-2w3 or H-2w17 were responders to mouse type II collagen, and only these strains developed arthritis after immunization with heterologous or autologous type II collagens. These findings indicate that the ability to mount an immune response against autologous type II collagen is a prerequisite for the susceptibility to collagen arthritis. A cross-reactive autoimmune response after immunization with various heterologous type II collagen may enhance further the development of arthritis.

Animals↗
PubMed1987

Isolation and characterization of neurokinin A, neurokinin A(3-10) and neurokinin A(4-10) from a neutral water extract of a metastatic ileal carcinoid tumour.

A metastasis to the right liver lobe of an argyrophil/argentaffin midgut carcinoid tumour in a patient with the classical carcinoid syndrome was examined for the presence of tachykinins other than substance P, using a specific antiserum. The extract was initially purified using SepPak cartridges, and subsequently subjected to cation-exchange chromatography on SP Sephadex C-25 which separated the immunoreactive material into two main components (components I and II). Both were further purified by anion-exchange chromatography on DEAE-Sephadex A-25, and by reverse-phase fast protein liquid chromatography. Component II was identified as neurokinin A by its immunochemical and chromatographic properties and amino acid sequence analysis. Component I consisted of two molecular forms which were identified as neurokinin A(3-10) and neurokinin A(4-10) by amino acid sequence analysis. The tumour tissue contained only small amounts of the eledoisin-like peptide that has earlier been demonstrated in mammalian tissues. Although this component behaved like the nonmammalian peptide eledoisin on reverse-phase HPLC and on reverse-phase ion-pair chromatography, eledoisin-specific antiserum E2 indicated that eledoisin-like peptide is not identical to eledoisin. Neurokinin A in carcinoid tumours has an N-terminal heterogeneity; this multiplicity constitutes a further support for the hypothesis that carcinoid tumours produce a number of tachykinins which may be present in different relative amounts in individual patients and may contribute to the individual differences in symptomatology.

Carcinoid Tumor↗
PubMed1987

Structure and organization of the murine band 3 gene.

The Band 3 protein mediates the reversible exchange of chloride and bicarbonate anions across the plasma membrane of erythrocytes, and probably, certain epithelial cells. It also serves to anchor the spectrin cytoskeleton to the plasma membrane via its association with ankyrin. We have isolated and largely sequenced the 17-kilobase murine Band 3 gene. We show that this gene is present in a single copy in the mouse genome and have identified and mapped the 19 intervening sequences. The locations of the intron/exon junctions in the Band 3 mRNA correlate with predicted structural features of the erythrocyte Band 3 protein structure and membrane topology. One of the introns within this gene contains a single copy of a murine Alu-type high dispersed sequence, in addition to several unusual tandemly repeated sequences.

Animals↗
PubMed1987

Reduced allorecognition of adenovirus-2 infected cells.

The early region 3 of adenovirus 2 encodes the membrane glycoprotein E19. This protein specifically binds class I transplantation antigens of a variety of species. Concomitant with this interaction the intracellular transport of newly synthesized class I heavy chains is abrogated. At late stages of the virus infection this leads to a notable decrease in the cell surface expression of class I antigens. We have studied how infection with adenovirus 2 influences target cell recognition by alloreactive cytolytic T lymphocytes. We found that the E19 protein-induced reduction of the HLA-B7 cell surface expression led to a greatly reduced lysis of the infected cells. These findings support our hypothesis that the E19 protein has evolved to facilitate the in vivo replication of the virus by reducing the expression of HLA class I antigens.

Adenoviridae Infections↗
PubMed1987

Variation of incorporation of [3H]orotic acid into the nucleotide and RNA fractions of different parts of the same liver lobe in the rat.

1. Anaesthetized rats were given [3H]orotic acid either intraperitoneally or via a catheter into the hepatic artery with or without degradable starch microspheres. 2. The radioactivity in the acid soluble and RNA fractions of five pieces of the left lateral liver lobes was determined. 3. A variation of the distribution of the precursor into the different parts of the same liver lobe was shown. 4. This variation was most pronounced (3000-17,000 cpm/micrograms in the acid soluble fraction) when the precursor was administered via the artery and without microspheres. 5. The correlation between the radioactivity in the acid soluble and RNA fractions within each liver piece was 0.85, 0.90 and 0.75 in the three groups respectively. 6. It is suggested that the variation of the distribution depends on circulatory differences within the liver.

Animals↗