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Isaksson M, Bruze M, Björkner B, Hindsén M, Svensson L. The benefit of patch testing with a corticosteroid at a low concentration. AMERICAN JOURNAL OF CONTACT DERMATITIS : OFFICIAL JOURNAL OF THE AMERICAN CONTACT DERMATITIS SOCIETY 1999; 10:31-3. [PMID: 10072336 DOI: 10.1016/s1046-199x(99)90090-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Patch testing with corticosteroid marker molecules is advocated because testing with all available corticosteroids is impossible in clinical practice. Most commonly used are budesonide, tixocortol pivalate, and hydrocortisone-17-butyrate. We have been patch testing not only with the three markers, but also with two corticosteroid mixes, each consisting of different concentrations of the three markers. OBJECTIVE We describe a patient allergic to tixocortol pivalate, who was diagnosed by using a lower patch test concentration that recommended, 0.1% in petrolatum, as well as a weak corticosteroid mix, 0.202%. METHODS The patient was patch tested to a standard series, including the two corticosteroid mixes and its three constituents. RESULTS None of the corticosteroid preparations were positive on the first ordinary reading day, day 3, whereas both tixocortol pivalate at 0.1% and the corticosteriod mix at 0.202% were positive on the second ordinary reading day, day 7, whereas all tested corticosteroids in the standard series gave positive reactions on d10. CONCLUSION The possible benefit of patch testing with a corticosteroid at a low concentration is supported, as is the significance of late readings beyond D4.
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Isaksson M, Bruze M, Goossens A, Lepoittevin JP. Patch testing with budesonide in serial dilutions: the significance of dose, occlusion time and reading time. Contact Dermatitis 1999; 40:24-31. [PMID: 9928801 DOI: 10.1111/j.1600-0536.1999.tb05972.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Budesonide is advocated as a marker molecule for corticosteroid contact allergy. When patch testing corticosteroids, one must consider their sensitizing potential but also their anti-inflammatory properties, as well as the possibility of different time courses for such properties. The dose-response relationship for budesonide was therefore investigated with regard to dose, occlusion time, and reading time. 10 patients were patch tested with budesonide in ethanol in serial dilutions from 2.0% down to 0.0002% with occlusion times of 48, 24, and 5 h. Readings were on D2, D4, and D7. The 48-h occlusion picked up most positive reactors, 8/10. The D4 reading (48-h occlusion) detected most positive reactors, 8/10, and here 0.002% picked up most contact allergies. Late readings favoured high concentrations. The "edge effect" was noted for several concentrations at early readings. Due to the individual corticosteroid reactivity, the dose-response relationship and the time courses of the elicitation and the anti-inflammatory capacity, several features may be explained, i.e., that lower concentrations may detect budesonide allergy better at early readings, that patients with an "edge reaction" can have positive reactions to lower concentrations.
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Isaksson M, Bruze M, Matura M, Goossens A. Reply. Contact Dermatitis 1998. [DOI: 10.1111/j.1600-0536.1998.tb05831.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Isaksson M, Persson LM. Contact allergy to hydrocortisone and systemic contact dermatitis from prednisolone with tolerance of betamethasone. AMERICAN JOURNAL OF CONTACT DERMATITIS : OFFICIAL JOURNAL OF THE AMERICAN CONTACT DERMATITIS SOCIETY 1998; 9:136-8. [PMID: 9601904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Contact allergy to corticosteroids is not uncommon. As the clinical pattern that the patients exhibit may be misleading, the discovery at patch testing may be unexpected and solely a result of the fact that marker molecules for corticosteroid contact allergy are incorporated into standard series and that tests are read twice, on D3/4 and D7. OBJECTIVE We describe a patient allergic to hydrocortisone who was given a cross-reacting corticosteroid, prednisolone, that led to a systemic contact dermatitis. The patient cleared when betamethasone, a non¿Ncross-reacting corticosteroid, was administered. METHODS The patient was patch tested to a standard series including tixocortol pivalate, and an extended corticosteroid series including betamethasone. RESULTS Patch testing with tixocortol pivalate provoked an allergic patch test reaction (+? D3, +D7), whereas betamethasone did not. CONCLUSION Our patient's allergy was undiagnosed for 5 years, and it was not until she was given a cross-reacting corticosteroid, which led to exacerbation of her dermatitis, that her physician suspected corticosteroid allergy. The incorporation of marker molecules for the detection of corticosteroid contact allergy into standard series with two reading occasions, 3 to 4 days apart, is advocated.
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Isaksson H, Isaksson M, Ludwigs U, Ruiz H, Skalshöi-Hansen K. [The European Parliament wants to legitimize quackery!]. LAKARTIDNINGEN 1998; 95:140-1. [PMID: 9467279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Isaksson M. [The Swedes do not want to privatize the ambulances. Interview by Lise Leonhardt Hjorth]. SYGEPLEJERSKEN 1997; 97:15. [PMID: 9444248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Isaksson M, Bruze M, Matura M, Goossens A. Patch testing with low concentrations of budesonide detects contact allergy. Contact Dermatitis 1997; 37:241-2. [PMID: 9412759 DOI: 10.1111/j.1600-0536.1997.tb02448.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Sjögren HO, Isaksson M, Willner D, Hellström I, Hellström KE, Trail PA. Antitumor activity of carcinoma-reactive BR96-doxorubicin conjugate against human carcinomas in athymic mice and rats and syngeneic rat carcinomas in immunocompetent rats. Cancer Res 1997; 57:4530-6. [PMID: 9377565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The internalizing monoclonal antibody BR96 was conjugated to the anticancer drug doxorubicin (DOX) using an acid-labile hydrazone bond to DOX and a thioether bond to the monoclonal antibody. The resulting conjugate, termed BR96-DOX, binds to a tumor-associated Lewis(y) antigen that is abundantly expressed on the surface of human carcinoma cells. BR96-DOX binds to RCA, a human colon carcinoma cell line, and BN7005, a transplantable colon carcinoma induced in a Brown Norway (BN) rat by 1,2-dimethyl-hydrazine. BR96-DOX produces cures of established s.c. RCA human colon carcinomas in athymic mice and rats. BR96-DOX also cured both s.c. and intrahepatic BN7005 tumors in immunocompetent BN rats. Unconjugated DOX, given at its maximum tolerated dose, and matching doses of nonbinding IgG-DOX conjugate were not active against RCA or BN7005 carcinomas. An anticonjugate antibody response was produced in BN rats treated with BR96-DOX. However, this could be largely prevented by administering the immunosuppressive drug deoxyspergualin. These results confirm the concept of antibody-directed therapy in models in which the targeted antigen is expressed both in normal tissues and tumors. The findings in BN7005 further demonstrate efficacy of BR96-DOX therapy in a model in which the tumor is syngeneic and the host is immunocompetent.
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Panagopoulos I, Lassen C, Isaksson M, Mitelman F, Mandahl N, Aman P. Characteristic sequence motifs at the breakpoints of the hybrid genes FUS/CHOP, EWS/CHOP and FUS/ERG in myxoid liposarcoma and acute myeloid leukemia. Oncogene 1997; 15:1357-62. [PMID: 9315104 DOI: 10.1038/sj.onc.1201281] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have sequenced the breakpoint regions in one acute myeloid leukemia (AML) with t(16;21)(p11;q22) resulting in the formation of a FUS/ERG hybrid gene and in four myxoid liposarcomas (MLS), three of which had the translocation t(12;16) (q13;p11) and a FUS/CHOP fusion gene and one with t(12;22;20)(q13;q12;q11) and an EWS/CHOP hybrid gene. The breakpoints were localized to intron 7 of FUS, intron 1 of CHOP, an intronic sequence of ERG and intron 7 of EWS. In two MLS cases with t(12;16) and in the AML, the breaks in intron 7 of FUS had occurred close to each other, a few nucleotides downstream from a TG dinucleotide repeat region. The break in the two MLS had occurred in the same ATGGTG hexamer and in the AML 40 nucleotides upstream from the hexamer. The third case of t(12;16) MLS had a break upstream and near a TC-dinucleotide repeat region and a sequence similar to the chi bacterial recombination element was found to flank the breakpoint. In the MLS with the EWS/ CHOP hybrid gene, the break in intron 7 of EWS had occurred close to an Alu sequence. Similarly, in all 4 MLS, the breaks in intron 1 of CHOP were near an Alu sequence. No Alu or other repetitive sequences were found 250 bp upstream or downstream from the break in the ERG intron involved in the AML case. In the AML, the MLS with ESW/CHOP and in one MLS with FUS/CHOP there were one, two and six, respectively, nucleotide identity between the contributing germline sequences in the breakpoint. In the other two MLS cases, two and three extra nucleotides of unknown origin were inserted between the FUS and CHOP sequences. At the junction and/or in its close vicinity, identical oligomers, frequently containing a trinucleotide TGG, were found in both partner genes. Our data thus show that all four genes-FUS, EWS, CHOP and ERG-contain characteristic motifs in the breakpoint regions which may serve as specific recognition sites for DNA-binding proteins and have functional importance in the recombination events taking place between the chromosomes. Different sequence motifs may, however, play a role in each individual case.
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Garkavij M, Tennvall J, Strand SE, Sjögren HO, JianQing C, Nilsson R, Isaksson M. Extracorporeal whole-blood immunoadsorption enhances radioimmunotargeting of iodine-125-labeled BR96-biotin monoclonal antibody. J Nucl Med 1997; 38:895-901. [PMID: 9189138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
UNLABELLED This study investigates the efficacy of tumor radioimmunotargeting with 125I-labeled BR96-biotin monoclonal antibody using a new method, whole-blood immunoadsorption (WBIA), based on direct adsorption of unbound monoclonal antibody (MAb) from blood without preceding separation of plasma. METHODS Highly tumor-reactive, internalizing, chimeric BR96 MAb of isotype IgG1 binds to a tumor-associated Lewis-type (Le(Y)) cell surface antigen. Forty-six Brown Norwegian male rats were inoculated intramuscularly and beneath the liver or kidney capsule with syngeneic rat colon carcinoma BN7005, expressing Lewis-type antigen, and investigated. The rats were injected intravenously with 3.5-4.5 MBq 125I-labeled BR96-biotin. Twenty of the rats underwent WBIA starting 5 or 12 hr after injection. About six blood volumes were passed through an avidin-gel adsorption column during 2 hr. RESULTS By using WBIA, whole-body radioactivity was reduced by 50%, and plasma activity by 85%. Both directly after completion of WBIA and 33 hr later, the activity uptake in tumors manifested only a nonsignificant decrease as compared with corresponding controls (p > 0.05) and had approximately similar time-activity curves. Uptake ratios for tumor (T):bone marrow, T:liver, T:kidney and T:lung were enhanced 2.3- to 3.5-fold in all three tumor models, as compared with controls. The ratio of liver tumor to bone marrow was improved from 10:1 to 30:1. CONCLUSION This new method of WBIA yields significantly improved radioimmunotargeting of highly tumor-reactive, internalizing MAb BR96.
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Garkavij M, Tennvall J, Strand SE, Nilsson R, Lindgren L, Chen J, Isaksson M, Eriksson H, Sjögren H. Extracorporeal immunoadsorption from whole blood based on the avidin-biotin concept. Evaluation of a new method. Acta Oncol 1996; 35:309-12. [PMID: 8679261 DOI: 10.3109/02841869609101646] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study of 36 rats with rat colon adenocarcinoma transplants was carried out to investigate the efficacy of a new method of whole blood immunoadsorption (WBIA) in removing biotinylated monoclonal antibodies (MAbs) directly from unseparated blood, in order to increase 'the tumor/normal-tissue uptake ratio', as compared with extracorporeal immunoadsorption (ECIA) of antibodies from plasma. Compared with the ECIA system, the overall volume of the WBIA system (comprising only a pump, an adsorption column, a drop-chamber and tubings) was less (3.6 vs. 6.2 ml), and procedure duration 2 h less. The 17 rats undergoing the WBIA procedure, started 12 h after i.v. injection of 4.0-4.5 MBq 125I-BR96-biotin, manifested neither hemolysis nor any other complication; no signs of organ edema were found at dissection; whole body and blood radioactivity values were reduced by 51% and 89.5%, respectively. The WBIA method was as effective as ECIA, but technically simpler, safer and more reliable.
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Temvall J, Garkavij M, Strand S, Sjögren H, Chen J, Nilsson R, Linagren L, Isaksson M, Eriksson H. 134 Enhanced tumor radioimmunotargeting of chimeric 125I-BR96-biotin in a syngeneic rat tumor model using whole blood extracorporeal immunoadsorption (ECIA). Eur J Cancer 1995. [DOI: 10.1016/0959-8049(95)95389-n] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bruze M, Isaksson M, Edman B, Björkner B, Fregert S, Möller H. A study on expert reading of patch test reactions: inter-individual accordance. Contact Dermatitis 1995; 32:331-7. [PMID: 7554879 DOI: 10.1111/j.1600-0536.1995.tb00621.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
To diagnose allergic or irritant contact dermatitis, a clinically relevant contact allergy has to be demonstrated or ruled out, respectively. Although patch testing has been used for 100 years, it remains the method of choice for diagnosing contact allergy. A disadvantage of patch testing is that reading is subjective, based on inspection and palpation of the test area, implying that the assessment is subject to the reader's knowledge and experience. This study was carried out to investigate the accordance in reading patch test reactions between 5 dermatologists. 4 groups, each with 10 patients, participated. Within each group, all 10 were allergic to one and the same sensitizer; nickel, epoxy resin, ethylenediamine, or Kathon CG. The sensitizers were tested in serial dilutions and applied randomly to the back. The tests were read independently by the dermatologists in a blinded fashion. A protocol was used where the dermatologists had to note the presence of the morphological features erythema, infiltration, papules, vesicles, and bullae. In this way, it was possible to allocate the various readings into 4 classification systems, 3 European and one American, although the definition of the various classifications might differ slightly. Based on the readings and classifications, it was possible to calculate the degree of accordance within the 4 systems used. It was also possible to analyze the degree of accordance for the various morphological features. Total accordance for the 5 reading dermatologists for positive and negative test reactions was noted in 36% and 46%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Bruze M, Isaksson M, Dooms-Goossens A. The influence of patch tests with clobetasol propionate on adjacent patch test reactions. Contact Dermatitis 1995; 32:167-70. [PMID: 7774190 DOI: 10.1111/j.1600-0536.1995.tb00809.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Contact allergy to corticosteroids now seems frequent among patients being patch tested. As corticosteroids are intrinsically anti-inflammatory, we investigated whether patch tests with a potent corticosteroid might suppress simultaneous adjacent patch test reactions to another allergen. Nickel-sensitive subjects were patch tested with an aqueous dilution series of nickel in duplicate, adjacent to patch tests with clobetasol propionate 1% in ethanol and with ethanol, respectively. Statistical evaluation of the results obtained in 2 different centers, using their own patch test techniques, did not reveal any suppression of the positive nickel patch test reactions.
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Isaksson M, Bruze M, Gruvberger B, Ljunggren B. Quinine and quinidine photoproducts can be identical. Acta Derm Venereol 1994; 74:286-8. [PMID: 7976088 DOI: 10.2340/0001555574286288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Quinine and its d-isomer quinidine can both cause contact allergy as well as photoallergy. Contact allergic cross-reactions between quinine and quinidine are uncommon. In allergic photosensitization the two isomers cross-react, suggesting the possibility that quinine and quinidine after UV exposure are converted to one or more common sensitizing photoproducts. Solutions of quinine and quinidine at 0.1% in ethanol 99.5% were exposed to UVA for 14 h (total dose 201.6 J/cm2). Using thin-layer chromatography, we identified 8 and 6 photoproducts from irradiated quinine and quinidine, respectively. Five of these photoproducts were seen in both chromatograms. An identical pattern with four photoproducts was found for both irradiated solutions when these were subjected to analysis in a high-performance liquid chromatography system. This study indicates that photoproducts from irradiated quinine and quinidine can be identical. This would explain the differences in the cross-reactivity pattern between contact and photocontact sensitization clinically.
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Isaksson M, Bruze M, Björkner B, Niklasson B. Contact allergy to Duraphat. SCANDINAVIAN JOURNAL OF DENTAL RESEARCH 1993; 101:49-51. [PMID: 8441896 DOI: 10.1111/j.1600-0722.1993.tb01646.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Skin-sensitizing rosin is present in Duraphat, a fluoride varnish used all over the world. Two cases of hypersensitivity to Duraphat are presented: a dental nurse with dermatitis of the hand and a patient with allergic contact stomatitis.
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Lindgren BF, Isaksson M, Stern I, Hall K. Insulin-like growth factor binding protein-1 from Hep G2 cells is potently inhibited by the truncated IGF-I analogue des-(1-3) IGF-I. ACTA ENDOCRINOLOGICA 1993; 128:81-7. [PMID: 7680515 DOI: 10.1530/acta.0.1280081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Des-(1-3) insulin-like growth factor-I (IGF-I) is an IGF analogue lacking aminoacid 1 to 3 which displays reduced binding to insulin-like growth factor binding protein-1 (IGFBP-1). A greater inhibition of immunoreactive IGFBP-1 was obtained with des-(1-3) IGF-I (10 ng/ml) in Hep G2 medium when incubated in Eagle's Modified Essential Medium (EMEM) without phenolred compared to EMEM with phenolred; EMEM without phenolred was chosen for further experiments. Des-(1-3)IGF-I decreases dose dependently the concentration of IGFBP-1, with a maximal effect at 3-10 micrograms/l when incubated for 24 h; 10 micrograms/l of des-(1-3)IGF-I caused a small but significant inhibition of IGFBP-1 after 8 h incubation and this inhibition was 41% and 33% of controls after 14 and 19 h incubation. The relative potencies at 16 h of incubation of IGF-I and insulin in suppressing IGFBP-1 in comparison to des-(1-3)IGF-I were 0.41 (0.25-0.78) and 0.08 (0.01-0.26), respectively. A dose-dependent decrease of IGFBP-1 mRNA to 30% of control was observed after 4 h incubation with 0.1-10 micrograms/l des-(1-3)IGF-I. Changes of glucose concentration (0-20 mmol/l) in the medium did not affect the IGFBP-1 concentration in the medium. In summary: Des-(1-3)IGF-I was tenfold more potent than insulin, and threefold more potent than IGF-I in decreasing IGFBP-1 concentration in medium conditioned by Hep G2 cells.
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Ljunggren B, Hindsén M, Isaksson M. Systemic quinine photosensitivity with photoepicutaneous cross-reactivity to quinidine. Contact Dermatitis 1992; 26:1-4. [PMID: 1600732 DOI: 10.1111/j.1600-0536.1992.tb00859.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A 75-year-old man developed an eczematous eruption on the face and dorsal aspects of the hands one July after 3 weeks' treatment with quinine, 0.25 g nightly, for nocturnal leg cramps. The photoreaction cleared within a week of quinine being stopped. UVA and UVB erythema threshold determinations, after the acute episode had subsided, were normal. A photopatch test was positive for irradiated quinine down to a concentration of 0.01% and for unirradiated quinine to 0.5%. The test with the isomer quinidine was positive only when irradiated, down to a concentration of 0.01%. Preirradiated samples of quinine and quinidine were negative. Whereas in contact allergy quinine and quinidine usually do not cross-react, after systemic photosensitization, the 2 isomers probably form a common photoproduct, accounting for the cross-reactivity.
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Löw H, Crane FL, Grebing C, Isaksson M, Lindgren A, Sun IL. Modification of transplasma membrane oxidoreduction by SV40 transformation of 3T3 cells. J Bioenerg Biomembr 1991; 23:903-17. [PMID: 1663950 DOI: 10.1007/bf00786008] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Transformation of 3T3 cells by SV40 virus changes the properties of the transplasma membrane electron transport activity which can be assayed by reduction of external ferric salts. After 42 h of culture and before the growth rate is maximum, the transformed cells have a much slower rate of ferric reduction. The change in activity is expressed both by change in Km and Vmax for ferricyanide reduction. The change in activity is not based on surface charge effect or on tight coupling to proton release or on intracellular NADH concentration. With transformation by SV40 virus infection the expression of transferrin receptors increases, which correlates with greater diferric transferrin stimulation of the rate of ferric ammonium citrate reduction in transformed SV40-3T3 cells than in 3T3 cells.
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Isaksson M, Ljunggren B. Ultraviolet B irradiation inhibits the induction of photoallergy to systemically administered quinidine in the mouse. PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 1991; 8:164-8. [PMID: 1814427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In albino mice photosensitized to quinidine, 100 mg/kg by intraperitoneal injection, pretreatment of the induction area with ultraviolet B (UVB) on 3 consecutive days was shown to significantly reduce the inflammatory response when the mice were challenged at a distant site 1 week later. Mice controlled for phototoxicity did not react. The inhibition was dose-dependent within the UVB dose range tested (0.05-1.0 J/cm2 x 3), being almost complete with the highest doses. Inhibition, although somewhat less pronounced, was also seen when an area on the back, distant from the induction site, was preirradiated following a similar protocol. The reduced response at elicitation persisted when the time to challenge was increased up to 4 weeks. At 5 weeks, a second attempt to photosensitize the previously inhibited animals failed, suggesting that a state of tolerance had been acquired. The timing of the UV exposure in relation to the photoactive chemical is critically important in determining whether an exposure promotes or inhibits photoallergic sensitization.
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Arheden K, Mandahl N, Strömbeck B, Isaksson M, Mitelman F. Chromosome localization of the human oncogene INT1 to 12q13 by in situ hybridization. CYTOGENETICS AND CELL GENETICS 1988; 47:86-7. [PMID: 3281802 DOI: 10.1159/000132513] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The human oncogene INT1 has been mapped to chromosome band 12q13 by in situ hybridization. The precise localization of this gene is of particular interest, since the region 12q13----q14 has been reported to be involved in chromosomal rearrangements in lipomas, myxoid liposarcomas, pleomorphic adenomas, and myomas. The involvement of this region in both benign and malignant tumors suggests a common pathogenetic pathway in which changes affecting INT1 may be an important step.
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Lima-de-Faria A, Arnason U, Widegren B, Isaksson M, Essen-Möller J, Jaworska H. DNA cloning and hybridization in deer species supporting the chromosome field theory. Biosystems 1986; 19:185-212. [PMID: 3022841 DOI: 10.1016/0303-2647(86)90039-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The Cervidae show the largest variation in chromosome number found within any mammalian family. The eight species of deer which are the subject of this study vary in chromosome number from 2n = 70 to 2n = 6. Three species of Bovidae are also included since they belong to a closely related family. Digestion of nuclear DNAs with the restriction endonucleases Hae III, Hpa II, Msp I, Eco RI, Xba I, Pst I and Bam HI reveals that there is a series of highly repetitive sequences forming similar band patterns in the different species. There are two bands (1100 and 550 base pairs) which are common to all species although the two families separated more than 40 million years ago. To obtain information on the degree of homology among these conserved sequences we isolated a Bam HI restriction fragment of approximately 770 base pairs from red deer DNA. This sequence was 32P labeled and hybridized by the Southern blot technique with DNAs cleaved with Bam HI, Eco RI, Hpa II and Msp I. Moreover, the same sequence was cloned in the plasmid vector pBR322 nick translated with 32P and hybridized with the DNAs of 8 species of Cervidae and 3 of Bovidae. The same cloned probe was labeled with 3H and hybridized in situ with the metaphase chromosomes of red deer (2n = 68) and Muntiacus muntjak (2n = 7 male). Homologies are still present between the highly repetitive sequences of the 8 species of Cervidae despite the drastic reorganization that led to extreme chromosome numbers. Moreover, the cloned DNA sequence was found to occupy the same position, in the proximal regions of the arms, in both red deer (2n = 68) and M. muntjak (2n = 7 male) chromosomes. The ribosomal RNA genes and the centromeres in these species have also maintained their main territory despite the drastic chromosome reorganization. These results are experimental confirmation of the chromosome field theory which predicted that each DNA sequence has an optimal territory within the centromere-telomere field and tends to occupy this same territory following chromosome reorganization.
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