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Biomedical subjects

C Jansén

Publications and source records attributed to C Jansén.

At least 19 recordsLinked to original sources
PubMed1998

Differential regulation of the AP-1 family members by UV irradiation in vitro and in vivo.

We have examined the effect of UVB and solar-simulated irradiation on the expression of the AP-1 family of transcription factors and the cytokine IL-6 both in cell cultures and in human skin in vivo. UVB irradiation potently induced c-jun, junB and c-fos mRNA levels in vitro in HaCaT cells. IL-6 mRNA was induced in response to UVB irradiation 2-3 h later than c-jun, junB and c-fos mRNAs. In human skin in vivo, solar-simulated irradiation induced transiently junB expression. Genistein, a tyrosine kinase inhibitor, augmented the induction of c-jun and junB by UVB irradiation in HaCaT cells. The results of this study provide evidence that in addition to c-jun and c-fos, junB is also an essential component of the human UV-response. This study also suggests that UVB irradiation regulates the AP-1 family by several mechanisms and that the signalling mechanisms of UVB irradiation are considerably different from the ones used by UVC irradiation.

Acetylcysteine↗
PubMed1995

[Effect of sunlight on the skin--what have we learned?].

Ultraviolet radiation (UVR) exerts a variety of effects on the skin, most of which are inimical. Best known is the effect of UVB radiation which readily burns unprotected skin, but we now know that even UVA radiation may exert penetrating effects on the skin, as well as causing DNA damage and increased risk of cancer. The markedly increased incidence of basal cell and squamous cell carcinoma and malignant melanoma among fair-skinned Caucasians in industrialised countries is attributed to increased exposure to UVR. Sunscreen creams may have exacerbated the situation. Effective phototherapy is a useful product of photomedical research, and it can be further improved. Recently new perspectives were opened up in basic research into UVR, when it was found that repair of DNA lesions via different pathways orchestrates a series of cellular phenomena such as oncogene expression, acid radical defence, immunomodulation, apoptosis and pigmentation induction.

Cytokines↗
PubMed1989

Immediate decrease in antigen-presenting function and delayed enhancement of interleukin-1 production in human epidermal cells after in vivo UVB irradiation.

Human skin was irradiated in vivo with a single UVB dose (100 mJ/cm2 or 200 mJ/cm2) to examine simultaneously the antigen-presenting function and interleukin-1 (IL-1) production capacity of irradiated epidermal cells (EC). Suction blisters were produced on irradiated areas on days 0, 3 and 7 after UVB. Irradiated EC were harvested and co-cultured with autologous T lymphocytes in the presence of antigens (PPD, HSV) or mitogen (ConA). Culture supernatants were tested for IL-1 activity using the thymocyte comitogenity assay. We found that a single 200 mJ/cm2 dose of UVB caused an immediate suppression of the antigen-presenting function of EC, but no alteration in their IL-1 production capacity or surface marker expression (ATPase, CDI). PPD- and HSV-induced lymphocyte proliferation was decreased 70-80% and ConA-driven proliferation 30% when compared to non-irradiated EC. However, this suppression was restored on days 3 and 7 after UVB irradiation, this being coexistent with an increased capacity of EC to produce IL-1. It remains to be elucidated whether the immediate UVB-induced photoimmunosuppression observed in the present study is due to inhibitory mediators or impaired membrane function of EC or both.

Adult↗
PubMed1989

A clinical trial of PUVA treatment in oral lichen planus.

Seventeen patients with histologically confirmed oral lichen planus (LP) unresponsive to previous treatments were enrolled in a study on the feasibility of photochemotherapy in the treatment of oral LP. An Espe Uviolite apparatus originally designed for irradiation of light-cured dental composite fillings was used as the source of radiation. The wavelength range of the apparatus was 320-400 (UVA) nm. Two hours before irradiation, 8-methoxy-psoralen (0.6 mg/kg) was administered orally, treatments being given at intervals of 2-3 days. Subjective symptoms disappeared totally in 13 of 17 patients at a mean cumulative dose of 6.1 J/cm2. Two months after treatment with a mean total dose of 11.6 J/cm2, 12 of the 17 lesions had markedly improved. After 12-24 months of follow-up, complete clinical remission was found in 5 of the 17 patients, 7 patients were in partial remission and 5 remained only slightly improved. We conclude that PUVA treatment may be useful for treating recalcitrant oral LP but, until more extensive studies are performed, it must be considered as experimental.

Adult↗
PubMed1988

The Scandinavian multicenter photopatch study 1980-1985: final report.

At 16 different dermatology clinics in Scandinavia from 1980-1985, photopatch testing was performed on 1993 patients with suspected photodermatosis. The collective results are presented in this article. The most common cause of sun-related dermatosis was polymorphic light eruption (PLE) (38%), while secondary aggravation of pre-existing skin diseases was established in 16% of the patient group. Photocontact dermatitis (11%) and contact dermatitis (10%) were responsible for 274 and 369 positive test reactions (respectively) on photopatch testing using the SPDRG standard series. Musk ambrette and para-aminobenzoic acid were the leading photosensitizers, while perfume mixture, balsam of Peru and lichen mixture were the most frequent causes of contact sensitivity. The principal photoallergens and contact allergens in the PLE, persistent light reaction and actinic reticuloid groups are discussed, together with the problems, risks and possible mechanisms of induction of photosensitization in these patients. The incidence, causes and diagnostic and therapeutic implications of secondary sunscreen sensitivity in these groups are also addressed.

Clinical Trials as Topic↗
PubMed1987

Langerhans cell- and T-lymphocyte functions in patients with atopic dermatitis with disseminated cutaneous herpes simplex virus infection.

We studied whether Langerhans cell (LC)- and T-lymphocyte functions of atopic dermatitis (AD) patients are impaired. Our study groups consisted of 6 patients with AD with previous disseminated herpes simplex virus infection (AD + HSV), 8 patients with ordinary AD, and 5 healthy subjects. Suction blisters were performed on abdominal skin and LC isolated on the basis of their attachment to IgG-coated erythrocyte monolayers. Antigen-presenting function of purified LC was studied by measuring the proliferation of HSV-stimulated T cells. Langerhans cells were also used to stimulate T cells in autologous mixed cell reaction (AMCR). In addition, the production of epidermal cell thymocyte-activating factor (ETAF) by crude epidermal cells was measured. The HSV-induced T-cell proliferation in AD + HSV and AD patients was comparable with that of controls. The AMCR responses of patients with AD + HSV and AD were clearly diminished when compared with healthy controls. Patients with AD also produced significantly less ETAF than controls. Our results suggest that HSV antigen-presenting function of LC from patients with AD + HSV seems to be intact. Defective AMCR may reflect an abnormality in autoregulation and generation of effector cells and this together with decreased ETAF production may have pathogenetic significance in AD.

Antibodies, Viral↗
PubMed1986

Human epidermal Langerhans cells and peripheral blood monocytes. Accessory cell function, autoactivating and alloactivating capacity and ETAF/IL-1 production.

We compared the functional capacities of human epidermal Langerhans cells (LC) and peripheral blood monocytes. Epidermal sheets were obtained by a suction blister device. After enzymatic treatment LC were enriched by attaching them to IgG-located erythrocyte monolayers. On a per cell basis, LC were several times more efficient accessory cells than monocytes in augmenting nickel-and tuberculin (PPD)-induced T-cell proliferation. In mixed cell cultures LC stimulated both autologous and allogeneic T cells, whereas monocytes stimulated only allogeneic cells. In addition, LC were significantly more potent allogeneic stimulators than monocytes. Although monocytes were weaker accessory cells and allogeneic stimulators than LC, they induced higher interleukin 1 (IL-1) activities than LC-enriched or LC-depleted cells. These results indicate that there are functional differences between LC and monocytes and that antigen presentation and mediator secretion are not correlated.

Antigen-Presenting Cells↗
PubMed1985

[Phototherapy].

Explore the source record for details and available documents.

Humans↗
PubMed1982

The polymorphic phototest reaction.

One hundred tem patients with polymorphic light eruption (PMLE) and 58 control subjects were tested with an overdose of erythemogenic radiation. A morphologically abnormal phototest reaction was demonstrable in 72% of the patients with PMLE and in 9% of the control subjects. On the average, a dose of 3.8 times the patient's minimal erythemal dose was needed to produce the reaction. The most common findings in positive phototest reaction sites were edema and itching. A medium-pressure mercury lamp was shown to be as effective as a xenon arc lamp in producing the phototest reaction. The time of the reaction varied considerably in different patients, and frequent inspections of test sites were necessary to detect positive phototest reactions. When properly performed and interpreted, phototesting is a valuable diagnostic procedure for PMLE.

Adolescent↗