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H Hönigsmann

Publications and source records attributed to H Hönigsmann.

At least 73 records · Page 4Linked to original sources
PubMed1993

Lethal photosensitization by endogenous porphyrins of PAM cells--modification by desferrioxamine.

The effects of exogenous delta-aminolevulinic acid (ALA) on cultured PAM 212 cells were investigated. PAM cells exposed to ALA produce an excess of products of the heme biosynthesis pathway within hours. The endogenous porphyrins render the cells photosensitive in a time-, ALA dose- and irradiation-dependent manner. Independently of the ALA-induced photosensitized processes, ALA itself reduces the proliferation rate of PAM cells during the exponential growth phase. Iron deprivation by addition of the chelating agent desferrioxamine (df) accelerates the photosensitizing process, and thus makes it more efficient at lower ALA concentrations. The effects of df were compared with the effects of manganese-df and iron-df. The results indicate that iron trapping is the most important factor for the potentiation of ALA-stimulated photodynamic sensitization as well as for the dark toxicity. Iron complexing agents may thus be used to optimize ALA effects in the photodynamic treatment of cutaneous neoplasms with endogenous porphyrins.

Aminolevulinic Acid↗
PubMed1993

Results and tissue healing after copper-vapour laser (at 578 nm) treatment of port wine stains and facial telangiectasias.

Twenty-four patients with port wine stains (PWS), and 33 patients with facial telangiectasias were treated with a copper-vapour laser (CVL) operating at 578 nm. Good to excellent results were obtained in 52% of PWS and 69% of facial telangiectasias. Enzyme histochemistry revealed vessel-selective damage with energy densities up to 12 J/cm2, but a non-specific coagulation necrosis with higher fluences (> or = 15 J/cm2). With vessel-selective fluences only moderate blanching was obtained in two PWS. All other evaluated patients were treated using non-selective energy densities. Tissue healing was comparable with that after argon laser treatment. The theoretically correct wavelength (578 nm) alone appeared to be no guarantee of vessel-selective damage. The laser employed lacked adequate power (only 1.3 W maximum) to transmit sufficient energy into the tissues in a short exposure time. However, the clinical results confirm the value of the CVL in the treatment of superficial cutaneous angiodysplasias.

Adolescent↗
PubMed1993

UVA does not photoreactivate pyrimidine dimers in cultured human fibroblasts.

Pyrimidine dimers were induced in duplicates of cultured human skin fibroblasts by irradiation with various doses of UVB radiation. Subsequently, one set of cells was further exposed to either 5 or 10 J/cm2 of UVA radiation to assess the photoreactivating activity of this spectral range in a human cell system. Following irradiation, pyrimidine dimers were quantified in all cells by determining the number of endonuclease-sensitive sites (ESS). No difference in the yield of ESS was observed between cells which had been irradiated with UVB only as compared to cells which subsequently had been exposed to 5 or 10 J/cm2 UVA. In contrast, subsequent exposure of UVB-irradiated cells of Monodelphis domestica to 10 J/cm2 UVA resulted in an almost 50% reduction of UVB-induced pyrimidine dimers. These data indicate that UVA does not induce photoenzymatic repair in human fibroblasts.

Adult↗
PubMed1992

Severe sun sensitivity and the presence of antinuclear antibodies in patients with polymorphous light eruption-like lesions. A form fruste of photosensitive lupus erythematosus?

BACKGROUND: Initial lesions seen in some cases of lupus erythematosus may simulate the clinical features of polymorphous light eruption. OBJECTIVE: To evaluate the significance of antinuclear antibody screening in patients with polymorphous light eruption or to find better methods to define patients at risk to have lupus erythematosus, we analyzed the data of 198 patients with polymorphous light eruption. METHODS: History, type, and persistence of skin lesions were reviewed, and serologic variables, the minimal erythema dose, and the ultraviolet action spectrum for inducing skin lesions were determined. RESULTS: The morphologic features of skin lesions and results of phototesting were consistent with previously published characteristics of patients with polymorphous light eruption. Twenty-eight (14%) had high titers of antinuclear antibody (greater than or equal to 1:80). We found a highly significant correlation between severe sun sensitivity and the presence of high antinuclear antibody titers. Of these patients with severe sun sensitivity and high titers of antinuclear antibody, in three the diagnosis of systemic lupus erythematosus could be established according to American Rheumatism Association criteria. CONCLUSION: These results suggest that a combination of severe sun sensitivity and high titers of antinuclear antibody may characterize a subset of sun-sensitive patients with some features of lupus erythematosus.

Adult↗
PubMed1992

8-MOP vs 5-MOP.

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5-Methoxypsoralen↗
PubMed1991

Photopatch testing: the 5-year experience of the German, Austrian, and Swiss Photopatch Test Group.

A cooperative photopatch test study was conducted by 45 dermatologic centers in Austria, Germany, and Switzerland. Results obtained from 1985 to 1990 are presented. A standard photopatch test tray of 32 substances was applied to the back of patients with suspected photosensivity. After applications for 24 hours, test sites were irradiated with 10 joules/cm2UVA. Unirradiated controls were included. Readings were performed immediately and 24, 48, and 72 hours after irradiation; responses were qualitatively graded on a 4-point scale. All data were stored and processed by a computer. With computer-assisted analysis of reaction patterns photoallergic reactions were identified and distinguished from phototoxic reactions. Data of 1129 patients were evaluated. Among a total of 2859 positive test reactions in 870 patients, 2041 in 778 patients were found to be photoinduced and 818 in 413 patients were contact reactions; 108 reactions in 83 patients were classified as photoallergic. Nonsteroidal anti-inflammatory drugs, disinfectants, sunscreens, phenothiazines, and fragrances caused most often photoallergic reactions. Many unspecific phototoxic reactions were induced by tiaprofenic acid, promethazine, carprofen, chlorpromazine, fenticolar, wood balsam of Peru, and perfumes. Despite the distinction between photoallergic and phototoxic responses, many test reactions lacked relevance for the patients' dermatoses.

Adolescent↗
PubMed1991

Photochemotherapy for severe psoriasis without or in combination with acitretin: a randomized, double-blind comparison study.

In a randomized, double-blind comparative study 60 patients with severe, widespread psoriasis were treated either with photochemotherapy (PUVA) alone or in combination with acitretin. Forty-eight patients completed the study; of these, 25 received placebo combined with PUVA and 23 received acitretin with PUVA. Marked or complete clearing of psoriasis occurred in 80% of the patients (20 of 25) without acitretin and in 96% of the patients (22 of 23) with adjunctive acitretin administration. The mean cumulative UVA dose given to patients in the acitretin-PUVA group was 42% less than that required for patients in the placebo-PUVA group. We conclude that acitretin substantially augments the efficacy of photochemotherapy in the treatment of severe psoriasis.

Acitretin↗
PubMed1991

Relative efficacy of 335 and 365 nm radiation in photochemotherapy of psoriasis.

The action spectrum for the induction of phototoxic erythema by treatment with 8-methoxypsoralen (8-MOP) and UVA peaks at around 335 nm. Because earlier investigations reported peak phototoxic activity at 365 nm, we compared the antipsoriatic efficacy of 335 and 365 nm in an oral psoralen photochemotherapy (PUVA) regimen using a monochromator. PUVA with 335 nm was twice as effective as with 365 nm, with respect to both erythemogenicity and the cumulative dose required for clearing psoriasis. However, 335 and 365 nm were equally effective if delivered in equal erythema doses. It appears that in human skin the antipsoriatic activity of 8-MOP parallels its erythemogenicity.

Dose-Response Relationship, Radiation↗
PubMed1990

Photochemotherapy improves chronic cutaneous graft-versus-host disease.

We have used oral psoralen photochemotherapy (PUVA) to treat four patients with chronic graft-versus-host disease of the skin, oral mucosa, and liver, who had responded only partially to long-term immunosuppressive therapy (prednisolone, cyclosporine, azathioprine). PUVA therapy was delivered to the entire skin but not to the oral mucosa, and immunosuppressive therapy was continued in all patients. Two patients' skin lesions improved considerably; the oral lesions healed and did not recur in one. Immunosuppressive therapy could be reduced in these two patients. One patient with sicca signs did not improve. One patient had to interrupt PUVA therapy because of side effects attributed to 8-methoxypsoralen (nausea and vomiting). No flare of acute cutaneous graft-versus-host disease was noted during PUVA therapy. Chronic graft-versus-host disease of the liver did not improve in any patient.

Adolescent↗
PubMed1990

Cyclosporin A in combination with photochemotherapy (PUVA) in the treatment of psoriasis.

Forty patients with relapsing plaque psoriasis involving more than 20% body surface were treated either with cyclosporin A (CyA) plus PUVA or the retinoid etretinate plus PUVA (RePUVA). They initially received either CyA (2 weeks) or etretinate (1 week) alone and then PUVA was given concomitantly until complete remission. The patients were monitored over a period of 6 months and any relapse recorded. With each combined treatment regimen, CyA plus PUVA and RePUVA, the patients cleared within comparable periods of time (mean treatment period of 5.3 vs. 4.7 weeks after initiation of therapy and 3.3 vs. 3.7 weeks after initiation of PUVA). However, the cumulative UVA dose required for clearance (110.9 J/cm2 vs. 62.1 J/cm2 (P less than 0.05)) and the incidence of severe and early relapses were significantly higher in the CyA cohort. Within 6 months severe relapses had occurred in 58% of CyA plus PUVA but only in 15% of RePUVA-treated patients (P less than 0.001). This suggests that the CyA plus PUVA regimen as performed in this study is less effective than RePUVA.

Adult↗
PubMed1990

Treatment of psoriatic arthritis by extracorporeal photochemotherapy.

Five patients with long-standing seronegative arthritis resistant to conventional therapy and who also had psoriasis of the skin were treated with photopheresis. This mode of treatment combines a lymphocyte-enrichment procedure with 8-methoxypsoralen-photochemotherapy. There was a marked in vitro effect on treated lymphocytes, with a reduction of viability, proliferation and mitogen response. There was a slight to moderate clinical improvement in four of the five patients with regard to the strength of grip, swelling, pain, morning stiffness, the dosage of non-steroidal anti-rheumatic drugs and the radiographical changes. The skin lesions did not respond to photopheresis. Short-term side-effects were minimal and consisted of a temporary sensitivity of the eyes to light and signs of circulatory dysregulation immediately after treatment. This experimental therapy has some measurable but not dramatic effect in improving psoriatic arthropathy.

Adult↗
PubMed1990

Phototherapy and photochemotherapy.

This is a review of present knowledge of the use of ultraviolet (UV) radiation in the treatment of skin diseases. Two methods are currently used: phototherapy with UVB, and photochemotherapy with UVA and psoralens as photosensitizers. Both forms have their place in dermatologic therapy. In particular, photochemotherapy has become a standard treatment for severe psoriasis, mycosis fungoides, vitiligo, and some other dermatoses; it is effective as prophylactic treatment in polymorphic light eruption and other photodermatoses. This report will focus on indications, possible mechanisms, and treatment results. In addition, the potential acute and chronic side effects of these therapies are reviewed with special emphasis on skin carcinogenesis.

Humans↗