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B T Gjertsen

Publications and source records attributed to B T Gjertsen.

45 records · Page 3Linked to original sources
PubMed1991

Double-blind, right/left comparison of calcipotriol and betamethasone valerate in treatment of psoriasis vulgaris.

The therapeutic efficacy and tolerability of calcipotriol ointment and betamethasone valerate ointment in psoriasis were compared in a multicentre, prospective, randomised, double-blind, right/left trial. 345 inpatients and outpatients with psoriasis vulgaris of symmetrical distribution were treated twice daily for 6 weeks with calcipotriol ointment 50 micrograms/g and betamethasone ointment 0.1% randomly assigned to opposite sides of the body. The main outcome measures--the psoriasis area and severity index (PASI), the investigators' assessments of erythema, thickness, and scaling, and the patients' own assessments of the overall response to treatment--were sought at weeks 2, 4, and 6. Both treatments significantly reduced the PASI scores and the investigator's assessment scores, but at each visit the PASI score was significantly (p less than 0.001) lower with calcipotriol than with betamethasone. At 6 weeks the mean PASI reduction was 68.8% with calcipotriol and 61.4% with betamethasone (95% confidence interval for difference 5.1-9.8, p less than 0.001). The scores for erythema, thickness, and scaling were significantly (p less than 0.001) lower with calcipotriol than with betamethasone at the end of treatment. The patients considered that 82.1% of calcipotriol-treated sides and 69.3% of betamethasone-treated sides had improved greatly or cleared up by the end of treatment (p less than 0.001). 57 adverse events were reported by 52 patients (15.1%). The most common adverse event, lesional/perilesional skin irritation, was slightly but not significantly (p = 0.12) more common with calcipotriol treatment. 15 (4.3%) patients were withdrawn from the study, 3 because of local adverse events. There were no changes in serum calcium during the study. Thus, calcipotriol ointment was superior to betamethasone valerate ointment in psoriasis vulgaris. Though long-term results are not yet available, calcipotriol holds great promise as an antipsoriatic agent.

Administration, Topical↗
PubMed1991

Programmed cell death (apoptosis) is induced rapidly and with positive cooperativity by activation of cyclic adenosine monophosphate-kinase I in a myeloid leukemia cell line.

Programmed death (apoptosis) of the rat myelocytic leukemic cell line IPC-81 was triggered by cyclic adenosine monophosphate (cAMP) analogs or by agents (cholera toxin, prostaglandins) increasing the endogenous cAMP level. The induction of cell death by cholera toxin was preceded by increased activation of cAMP-kinase. Cell lysis started already 5 hr after cAMP challenge and was preceded by internucleosomal DNA fragmentation and morphological changes characteristic of apoptosis. The cell suicide could be prevented by inhibitors of macromolecular synthesis. cAMP analogs induced cell death in a positively cooperative manner (apparent Hill coefficient of 2.9), indicating that triggering of the apoptotic process was under stringent control. There was a strong synergism between cAMP analogs complementing each other in the activation of cAMP-dependent protein kinase I (cAKI). No such synergism was noted for analogs complementing each other in the activation of cAKII. It is concluded that apoptosis can be induced solely by activation of cAKI. The IPC-81 cells expressed about four times more cAKI than cAKII. The expression of cAK subunits, on the protein and mRNA levels, was only minimally affected by cholera toxin treatment.

Animals↗
PubMed1991

The protein phosphatase inhibitor okadaic acid induces morphological changes typical of apoptosis in mammalian cells.

Okadaic acid, a specific and potent inhibitor of protein phosphatases 2A and 1, was tested for its effect on the morphology of a number of cell types: freshly isolated rat hepatocytes in suspension or in primary culture, the human mammary carcinoma cell line MCF-7, the human neuroblastoma cell line SK-N-SH, rat pituitary adenoma GH3 cells, and rat promyelocytic IPC-81 cells. All the cell types reacted within a few hours to okadaic acid in the concentration range 0.1 to 1 microM with profound morphological alterations. Among the changes noted were: condensation of chromatin, shedding of cell contents via surface bleb formation, redistribution and compacting of cytoplasmic organelles, formation of cytoplasmic vacuoles, and hyperconvolution of the nuclear membrane. In some cells nuclear fragmentation was noted. In addition, cells growing as monolayers rounded up and detached from the substratum. The treated cells had no swollen mitochondria and retained the ability to exclude trypan blue until the final stage of dissolution, supporting the hypothesis that the changes were apoptotic rather than necrotic. In hepatocytes the action of okadaic acid was mimicked by another phosphatase inhibitor, microcystin, and was accompanied by shrinkage of the cell volume, as judged by Coulter counter analysis. The action of phosphatase inhibitor was not abolished by protein synthesis inhibitors, Ca(2+)-depleted medium, or phorbol ester. Although hepatocyte DNA replication was very sensitive to inhibition by okadaic acid, DNA fragmentation was less pronounced in response to okadaic acid than other agents inducing the morphological appearance of apoptosis.

Animals↗
PubMedDate not supplied

Molecular regulation of cell death and therapeutic strategies for cell death induction in prostate carcinoma.

Many of the common molecular alterations associated with prostate cancer progression involve genes known to regulate cell death susceptibility. The significance of these molecular events is discussed in the context of developing and implementing new strategies designed to restore cell death susceptibility in prostate cancer cells and overcome therapeutic resistance.

Apoptosis↗
PubMedDate not supplied

Characterization of ribosomal P autoantibodies in relation to cell destruction and autoimmune disease.

Autoantibodies against the ribosomal P proteins are related to cell death and tissue destruction and are frequently exhibited in patients with systemic lupus erythematosus (SLE). In an attempt to explore the effect of tissue destruction on the induction of anti-P autoantibodies, we searched for anti-P autoantibodies by enzyme-linked immunosorbent assay in 201 antinuclear antibody (ANA)-positive individuals, in 10 patients with treated kidney SLE and in 45 acute leukaemia patients undergoing intensive chemotherapy. The autoantibody reactivity was further characterized using one- and two-dimensional immunoblot analysis and immunofluorescence. Anti-P were detected in 5.5% (11/201) of ANA-positive individuals, but not in kidney-affected SLE patients or in patients with leukaemia. Seven of 11 anti-P-positive patients had SLE (3/11), primary Sjögrens's syndrome (1/11) and other autoimmune diseases (3/11). A relation between disease activity and anti-P was suggested by follow-up examinations in one SLE patient, supported by the absence of anti-P autoantibodies in the 10 treated kidney SLE patients. Anti-P autoantibodies were detected by immunoblot in one patient with SLE indicating anti-P2 predominance and in the patient with Sjögrens's syndrome indicating anti-P1 predominance. Diverging humoral responses in these ANA- and anti-P-positive patients were further illustrated by immunofluorescence, elucidating varying nuclear reactivity and anti-P pattern. The observation of anti-P in individuals with active autoimmune disease, but not in patients with chemotherapy-induced cell damage, suggests that anti-P antibodies are part of a specific disease process, and not elicited as a response to cell destruction per se.

Adult↗
PubMedDate not supplied

Restoration of bax in prostate cancer suppresses tumor growth and augments therapeutic cell death induction.

BACKGROUND: Cancer cells are characterized by multiple genetic defects which result in altered rates of cell division, cell death and ability to differentiate. These same molecular alterations may also contribute to therapeutic resistance. We examined the potential contribution of the pro-apoptotic gene, bax, to suppressing the growth of prostate cancer cells. MATERIALS AND METHODS: The bax-deficient DU145 prostate cancer cell line was transfected with a hemagluttinin-tagged bax (HA-bax) vector to generate stable expressing bax clones. RESULTS: Ha-bax clones exhibited a significant reduction in tumor growth compared to vector control and parental cells when xenografted into nude mice. HA-bax clones were significantly more sensitive to cell death induction by cis-diamminedichloroplatinum, etoposide, doxorubicin and gamma-radiation than vector control cells. Sensitivity to paclitaxel remained unaltered in the Ha-bax cells. CONCLUSION: These findings suggest that bax may possess a tumor suppressor function in prostatic glandular epithelial cells and be an important determinant of sensitivity to therapeutic cell death induction.

Animals↗