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C T Jansen

Publications and source records attributed to C T Jansen.

29 records · Page 2Linked to original sources
PubMed1991

Production of interleukin-1 beta and tumour necrosis factor-alpha in patients with benign or malignant ovarian tumours.

To assess the role of interleukin-1 beta (IL-1 beta) and tumour necrosis factor alpha (TNF alpha) in the physiological host defence mechanisms against malignancies, the production of these cytokines in sera, ascitic and cyst fluids and in the tumour tissues of patients with benign or malignant ovarian tumours was studied. IL-1 beta was found neither in the sera nor in the ascitic fluids of these patients. It was also virtually absent from the cyst fluid samples. However, a mean value of 790 pg IL-1 beta/g tumour was found. Like IL-1 beta, TNF alpha was virtually absent in the serum samples. It was, however, detectable in the ascitic and cyst fluids and tumour tissues. The TNF alpha concentrations were highest in the tumour tissues, with a mean level of 328 pg/g tumour. When comparing the level of IL-1 beta and TNF alpha in patients with benign tumours to that seen in patients with malignant tumours, no differences in production were observed, regardless of the origin of the test samples. Our results indicate the production of IL-1 beta and TNF alpha in patients with ovarian tumours. More importantly, the finding that the production of these cytokines in patients with benign tumours is similar to that in patients with malignant tumours supports the conclusion that the production of these cytokines is more a nonspecific indicator of an inflammatory process than a specific response to a malignant process.

Adult↗
PubMed1987

Itch and malignancy prognosis in generalized pruritus: a 6-year follow-up of 125 patients.

When 125 patients with generalized pruritus were followed up for 6 years, 66% reported continuing pruritus. In four patients a malignancy had been identified at the time of the initial examination, and four other patients developed malignancies during the follow-up period. Seven of the patients died of the malignancy during the follow-up period. This incidence of malignancies does not differ significantly from the value expected in a general population, matched for age and sex. However, two of the cancers were lymphomas, and this incidence is significantly (p less than 0.01) higher than that expected in a similarly matched population. As a whole our study indicates that no significant overall increase of malignant neoplasms is to be expected in patients with generalized pruritus and, therefore, any general efforts for cancer follow-up screening seem unwarranted in patients with pruritus.

Female↗
PubMed1987

Ultraviolet B irradiation induces changes in the distribution and release of arachidonic acid, dihomo-gamma-linolenic acid, and eicosapentaenoic acid in human keratinocytes in culture.

There is increasing evidence that derivatives of 20-carbon polyunsaturated fatty acids, the eicosanoids, play an important role in the inflammatory responses of the human skin. To better understand the metabolic fate of fatty acids in the skin, the effect of ultraviolet B (UVB) irradiation (280-320 nm) on the distribution and release of 14C-labeled arachidonic acid, dihomo-gamma-linolenic acid, and eicosapentaenoic acid in human keratinocytes in culture was investigated. Ultraviolet B irradiation induced the release of all three 14C-labeled fatty acids from the phospholipids, especially from phosphatidylethanolamine, and this was accompanied by increased labeling of the nonphosphorus lipids. This finding suggests that UVB induces a significant liberation of eicosanoid precursor fatty acids from cellular phospholipids, but the liberated fatty acids are largely reincorporated into the nonphosphorus lipids. In conclusion, the present study suggests that not only arachidonic acid but also dihomo-gamma-linolenic acid, and eicosapentaenoic acid might be involved in the UVB irradiation-induced inflammatory reactions of human skin.

8,11,14-Eicosatrienoic Acid↗
PubMed1987

Evening primrose oil in the treatment of atopic eczema: effect on clinical status, plasma phospholipid fatty acids and circulating blood prostaglandins.

In a double-blind trial patients with atopic eczema received either oral evening primrose oil (EPO) (n = 14) or placebo (n = 11) for 12 weeks. In the EPO group a statistically significant improvement was observed in the overall severity and grade of inflammation and in the percentage of the body surface involved by eczema as well as in dryness and itch. Patients in the placebo group showed a significant reduction in inflammation. The patients receiving EPO showed a significantly greater reduction in inflammation than those receiving placebo. Evening primrose oil caused a significant rise in the amount of dihomogammalinolenic acid in the plasma phospholipid fatty acids. Plasma levels of TXB2, 6-keto-PGF1 alpha and PGE1, and the amount of TXB2 released into serum during clotting were not altered by evening primrose oil.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

Incorporation and distribution of dihomo-gamma-linolenic acid, arachidonic acid, and eicosapentaenoic acid in cultured human keratinocytes.

Human keratinocytes in culture were labelled with 14C-dihomo-gamma-linolenic acid, 14C-arachidonic acid or 14C-eicosapentaenoic acid. All three eicosanoid precursor fatty acids were effectively incorporated into the cells. In phospholipids most of the radioactivity was recovered, in neutral lipids a substantial amount, and as free unesterified fatty acids only a minor amount. The most of the radioactivity was found in phosphatidylethanolamine which was also the major phospholipid as measured by phosphorous assay. The incorporation of dihomo-gamma-linolenic acid and arachidonic acid into lipid subfractions was essentially similar. Eicosapentaenoic acid was, however, much less effectively incorporated into phosphatidylinositol + phosphatidylserine and, correspondingly, more effectively into triacylglycerols as compared to the two other precursor fatty acids. Once incorporated, the distribution of all three precursor fatty acids was relatively stable, and only minor amounts of fatty acids were released into the culture medium during short term culture (two days). Our study demonstrates that eicosanoid precursor fatty acids are avidly taken up by human keratinocytes and esterified into membrane lipids. The clinical implication of this finding is that dietary manipulations might be employed to cause changes in the fatty acid composition of keratinocytes.

8,11,14-Eicosatrienoic Acid↗
PubMed1985

Interrelationship of nickel and cobalt contact sensitization.

The possible modulating effect of previous nickel sensitization on subsequent cobalt sensitization, and vice versa, was studied in a guinea pig model, using an open epicutanous induction protocol. Challenge tests were made by both topical and systemic routes. Controls included animals sensitized to only one of the metals. Animals sensitized with both metals seemed to react more readily in patch testing to either allergen, as compared to mono-sensitized animals. Systemic challenge with cobalt revealed a significantly (p less than 0.05) higher reaction rate (70%) in animals originally sensitized to cobalt and subsequently to nickel, as compared to the reaction rate (20%) in cobalt mono-sensitized animals. The reverse order of double-sensitization (nickel first, cobalt subsequently) led to an intermediate cobalt sensitization rate (50%). These experimental data corroborate clinical findings which have indicated a mutual enhancing effect of nickel and cobalt contact sensitization in man, and provide an animal model for studying the underlying immunological processes.

Animals↗
PubMed1980

Treatment of chronic urticaria with an inhibitor of complement activation (cinnarizine).

Twenty-three patients with chronic urticaria were treated with cinnarizine, dexchlorpheniramine and placebo in a double-blind, crossover trial. Compared to placebo treatment both cinnarizine and dexchlorpheniramine caused a statistically significant improvement in the clinical symptoms (p less than 0.01). The two active drugs were found to be equally effective; however, cinnarizine was better tolerated. Both drugs appear to be useful in the treatment of chronic urticaria.

Adult↗
PubMed1980

Allergological risk factors as predictors of radiographic contrast media hypersensitivity.

An in-depth allergy history was obtained from 830 consecutive patients who were subjected to intravenous radiographic contrast medium (RCM) examinations. During the RCM examination 47 patients reacted with symptoms of hypersensitivity. In 26 of these (55.3%) a positive previous allergy history had been obtained. Although this finding was statistically significant, its practical value is severely hampered by the lack of selectivity, many of RCM non-reactors also giving positive allergy histories. A positive history of a previous reaction to RCM or to penicillin, however, was found to have more specificity in predicting a forthcoming hypersensitivity reaction to RCM.

Adolescent↗