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E Kristensen

Publications and source records attributed to E Kristensen.

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

The indirect leucocyte migration inhibition assay--an endotoxin-sensitive chemokinetic assay. Part II.

Depletion of agarose for endotoxins resulted in a low spontaneous migration of polymorphnuclear cells (PMNC). Re-addition of endotoxin, in casu lipopolysaccharide from E. coli 026:B6 (LPS), enhanced the spontaneous PMNC migration in a two-phased dose-response pattern, reaching maximum migration with LPS 1 x 10(-7) g/ml. Thus, the migration of PMNC under agarose seems to be a chemokinesis. Leucocyte migration inhibition factor (LIF), induced by PPD 50 micrograms/ml at endotoxin-free conditions, significantly reduced the PMNC migration compared to supernatants from control cultures, however not compared to the conventional limit of significance, MI = 0.80. With increasing PMNC migration there was an insignificant decrease in the MI. Addition of LPS, 1 x 10(-9) g/ml, during LIF induction caused a significant increase in LIF production, an effect which overshadowed the effect of PPD. Thus, the application of the conventional limit of significance, MI = 0.80, may result in false-negative or false-positive conclusions, depending upon the endotoxin contamination. A standardization of the endotoxin content in both steps of the indirect leucocyte migration inhibition assay seems mandatory in order to obtain a reliable and reproducible bioassay.

Adult↗
PubMed1984

Monocyte/T-cell interactions in Con A induced suppressor activity.

It is well documented that peripheral blood mononuclear cells (PBMC) can exert a Con A induced suppressor activity. The PBMC content of monocytes and its impact on registered suppressor activity of PBMC populations was examined. It was found that monocytes were unnecessary for the Con A induction of PBMC, and monocytes exhibited no Con A dependent suppressor potential. Furthermore, the presence of monocytes was found to be unnecessary for the Con A activated lymphocytes in order to exert their suppressor activity against the responder system, i.e. a Con A stimulated lymphoblast-transformation.

Concanavalin A↗
PubMed1983

A continued evaluation of the experimental conditions of a Con A-induced suppressor test system.

As shown previously, the suppressor activity measured by the Con A mixed lymphocyte culture assay exhibited a pronounced dependence on the technical parameters. In the present study it is shown that the length of the suppressor generation period, between 24 and 96 hours, had only a modest influence on the suppressor activity. However, when the activity in the responder system was high, there seemed to be a trend towards a slight increase of the suppressor level using a long generation period, i.e. 72 to 96 hours. An increase of the suppressor cell/responder cell ratio from 1/10 to 1/2 was followed by a rising suppressor level; a further increase of the ratio had no significant influence on the suppressor activity. A decrease of the ratio below 1/10 showed variable results: stimulation, no effect and suppressor activity. This variability might be due to technical reasons. DNA-synthesis was not necessary for the mechanisms involved in the Con A-elicited suppressor activity. No suppressor activity was obtained by Con A treatment of cells other than peripheral blood mononuclear cells, viz. autologous erythrocytes, allogeneic fibroblasts and allogeneic osteogenic sarcoma cells.

Concanavalin A↗
PubMed1983

The NK function elucidated with respect to effector cells, target cells and other immunological in vitro tests.

The microcytotoxicity assay and the leukocyte migration inhibition test were unable to reveal any specific reactivity in patients suffering from localized skin melanoma. The non-specific reactivity measured by the microcytotoxicity assay, the so-called NK activity was found to be associated to the cells bearing Fc receptors, irrespective of T and non-T identity. Further more the NK activity depends on the target cell used (established cell lines versus short-term cultures) and the lymphocyte/target cell ratio. The NK activity measured by microcytotoxicity assay and the leucocyte migration inhibition test were compared by simultaneous implementation of the two test systems. No correlation between significant leucocyte migration inhibition and NK activity was found. In a tumor neutralization test workout in a nude mouse model, it was found that patient lymphocytes decreased the number of tumor takes and increase the latency period. However, the specificity of these reactions were uncertain.

Antigens, Neoplasm↗
PubMed1982

Con A induced suppressor test: an evaluation of the experimental conditions.

The suppressor activity measured by the Con A mixed lymphocyte culture assay exhibited a pronounced dependence on the technical performance as well as a marked inter-individual variation. The activity exerted by the induced suppressor cells depended on the Con A concentration in the induction phase, and on the mitotic activity in the responder system. The patterns of suppressor activities obtained in an allogeneic and an autologous suppressor test system were identical. When calculating the suppressor activity it is suggested, that one uses the total activities of the test system, without any reduction corresponding to the activity of the mixed lymphocyte culture. It is suggested that the suppressor activity is expressed by a "suppressor profile" to make the results more applicable and the interpretation of different works meaningful.

Adolescent↗
PubMed1981

Disodium cromoglycate in the treatment of ulcerative colitis and Crohn's disease.

A controlled clinical study on disodium cromoglycate (DSCG) at a dose of 800 mg per day versus placebo was carried out in 141 patients with ulcerative colitis and 25 patients with Crohn's disease. Those of the ulcerative colitis patients who had been on sulphasalazine treatment continued that treatment during the trial (101 patients). Forty patients were intolerant of sulphasalazine. No patient received steroids during the last month before the study. Patients with Crohn's disease had their possible sulphasalazine treatment stopped before the trial. No beneficial effect of DSCG as compared with placebo was found, as the DSCG and the placebo group showed the same number of relapses in patients with a clinically inactive ulcerative colitis at the start of the trial and the same number of patients improving, deteriorating, and maintaining steady state in patients with clinically active ulcerative colitis at the start of the trial. There was no difference between relapse rate in DSCG and placebo groups in patients with Crohn's disease. No correlation between the eosinophil count in rectal mucosa and the outcome of the attack of ulcerative colitis could be demonstrated.

Clinical Trials as Topic↗
PubMed1981

Ethical aspects of clinical decision-making.

The aim of the present investigation was to describe and to classify significant ethical problems encountered by the members of the staff during the daily clinical work at a hospital medical department. A set of definitions was prepared for the purpose, including the definition of a 'significant ethical problem'. During a three month period 426 inpatients and 173 outpatients were admitted. Significant ethical problems were encountered during the management of 106 in-patients (25 per cent) and 9 out-patients (5 per cent). No significant difference was found between the frequency of ethical problems in female and male patients, but a positive correlation was noted between the number of problems and the patients' age. The problem types were classified according to a problem list. The results of this investigation suggest that greater attention must be paid to discussions about ethical problems among doctors and other categories of health personnel and that, among others, medical students ought to be taught the analysis of ethical problems.

Adolescent↗
PubMed1980

A comparative study of natural cytotoxicity and the leukocyte migration inhibition in human melanoma stages I and II.

White blood cells (lymphocytes or leukocytes) obtained from patients suffering from localized skin melanoma and from persons without malignant diseases were tested in the microcytotoxicity assay and leukocyte migration inhibition test using indentical relevant and control targets and antigens. In both test systems the reactivities recorded were found to be independent of target/antigen effector cell combinations, indicating that these interactions were nonspecific. The nonspecific reactivities measured by microcytotoxicity assay (natural cytotoxicity) and the leukocyte migration inhibition test were compared by the simultaneous implementation of the two test systems using white cells from the same blood sample. No correlation between significant leukocyte migration inhibition and significant natural cytotoxicity was found. It is concluded that the leukocyte migration inhibition test as well as the microcytotoxicity assay were neither specific nor mutually supplementary in evaluation of tumor-directed immunity in localized malignant melanoma.

Cell Migration Inhibition↗
PubMed1977

Mortality from ulcerative colitis in Denmark 1960-1969.

The mortality from ulcerative colitis in Denmark, calculated on the basis of the mortality statistics, was 0.5/100,000/year for the period 1960-69. The total material consists of 110 females and 108 males with ulcerative colitis. The mortality showed a decreasing tendency during the study period, but the fall was not significant. The distribution of the deaths between rural and urban areas corresponded to the distribution of the general population. 93% of the deaths took place in hospital, the greater part in the surgical departments.

Colitis, Ulcerative↗
PubMed1977

Prognosis of medically treated gastric ulcer. A prospective endoscopic study.

During the study period 1972-74 gastric ulcer was demonstrated by endoscopy in 114 patients, 54 of whom were included in the present study. Forty-two were excluded because of ulcer showing incipient healing, superficial erosions, manifest or suspected malignancy, or indication for surgery. Eighteen patients were not included because of advanced age, complicating diseases, or refusal to have further examinations. The study comprises a treatment phase and a follow-up phase. The treatment phase ran from the first encoscopic demonstration of gastric ulcer until complete healing. During this period the patient was treated with antacids and anticholinergics and, if required by his condition, admission to hospital. During the treatment phase, endoscopy was performed at intervals of from 3 to 6 weeks until healing. During the follow-up phase endoscopy was carried out in the event of dyspeptic complaints that might indicate recurrent ulcer. The healing and recurrence rates for various periods were calculated by the aid of the life-table method. After 1 mo. of treatment 13% of the aptients exhibited healing, after 2 mo. 29%, after 3 mo. 41%, and after 12 mo. 79%. In one month 9% of the primarily healed ulcers had recurred, in 2 mo. 15%, in 3 mo. 22%, and in 12 mo. 43%. The healing rate is appreciably lower than results reported in the literature, whereas the recurrence rate is in closer accordance with previous studies.

Adult↗