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Biomedical subjects

J Krutmann

Publications and source records attributed to J Krutmann.

At least 55 records · Page 3Linked to original sources
PubMed2000

Anaphylaxis to polyvinylpyrrolidone in an analgesic preparation.

A 32-year-old patient developed an anaphylactic reaction minutes after oral intake of acetaminophen-containing tablets (Doregrippin)). Scratch testing of the whole preparation was positive in contrast with the negative results obtained with pure acetaminophen. Therefore, scratch tests with the remaining drug components were performed and showed polyvinylpyrrolidone (PVP) to be the aetiological agent. Furthermore, specific IgE antibodies against PVP were demonstrated using a dot blot technique, thus ruling out a pseudo-allergic reaction. This case underlines the necessity to consider not only the active ingredient, but also additives as the causative agent.

Acetaminophen↗
PubMed2000

Phototherapy for atopic dermatitis.

The beneficial effects of ultraviolet (UV) radiation on atopic dermatitis has been appreciated for many years. While broadband UVB and psoralen UVA have been the mainstay of phototherapy for some time, the past 5 years have seen the introduction of phototherapeutic modalities, including UVA-1 and 311nm UVB. The best modality and mode of usage is dependent on the type of atopic dermatitis, severity and body site. T lymphocytes play an important role in disease pathogenesis and UV radiation has profound effects on skin and systemic immune responses.

Dermatitis, Atopic↗
PubMed2000

Neurotrophin-4 production by human epidermal keratinocytes: increased expression in atopic dermatitis.

Chronic inflammatory conditions of human skin, such as prurigo lesions of atopic dermatitis, are characterized clinically by intense pruritus and histologically by increased innervation. Regulation of skin innervation is thought to depend on neurotrophic factors. In this study, human skin cells were identified as a source of neurotrophins. Cultured keratinocytes expressed neurotrophin-4, whereas dermal fibroblasts expressed neurotrophin-3. In vitro stimulation with interferon-gamma, a marker cytokine for atopic eczema, induced keratinocyte neurotrophin-4 production, which was able to support growth of a neuroglioblastoma-derived cell line. In vivo, immunohistochemistry of human skin for neurotrophins showed neurotrophin-4 staining in the epidermal layer and neurotrophin-3 staining in the dermal compartment. Neurotrophin-4 but not neurotrophin-3 expression was markedly increased in interferon-gamma-injected skin. Prurigo lesions of atopic dermatitis skin were characterized by intense epidermal staining for neurotrophin-4, suggesting a pathophysiologic role for this neurotrophin in the increased innervation characteristic for these skin lesions. This study demonstrates differential expression and regulation of neurotrophins in human skin. It also identifies keratinocyte-derived neurotrophin-4 as a possible link between the immune and the nerve system of human skin.

Antibodies↗
PubMed2000

Ultraviolet A1 (340-400 nm) phototherapy for scleroderma in systemic sclerosis.

BACKGROUND: The presence of an inflammatory infiltrate consisting of helper T cells and a dysregulated matrix metabolism leading to excessive deposition of collagen are two pathogenetic factors responsible for the developments of fibrosis and sclerosis in patients with systemic sclerosis. In previous studies, ultraviolet A1 (UVA1) radiation phototherapy was shown to deplete skin-infiltrating T cells through the induction of T-cell apoptosis and to up-regulate the expression of matrixmetalloproteinase-1 (collagenase-1) in dermal fibroblasts. OBJECTIVE: Our purpose was to determine whether UVA1 phototherapy is effective for systemic sclerosis. METHODS: Lesional skin on the forearms of patients with systemic sclerosis (diffuse type, n =3; limited type, n =1) was exposed to medium-dose UVA1 radiation (60 J/cm(2)) daily. RESULTS: In all patients studied, UVA1 phototherapy-treated skin lesions were markedly softened after 9 to 29 exposures. Clinical improvement was associated with an increase in (1) joint passive range of motion values (P <.05), (2) skin temperature (thermography, P <.05), and (3) cutaneous elasticity (cutaneous elastometry, P <.05). Histologic evaluation of skin specimens obtained before and after UVA1 phototherapy revealed loosening of collagen bundles and the appearance of small collagen fibers. CONCLUSION: These studies indicate that UVA1 phototherapy is effective for patients with systemic sclerosis.

Aged↗
PubMed1999

Nuclear and cell membrane effects contribute independently to the induction of apoptosis in human cells exposed to UVB radiation.

UVB-induced DNA damage is a crucial event in UVB-mediated apoptosis. On the other hand, UVB directly activates death receptors on the cell surface including CD95, implying that UVB-induced apoptosis can be initiated at the cell membrane through death receptor clustering. This study was performed to measure the relative contribution of nuclear and membrane effects in UVB-induced apoptosis of the human epithelial cell line HeLa. UVB-mediated DNA damage can be reduced by treating cells with liposomes containing the repair enzyme photolyase followed by exposure to photoreactivating light. Addition of photolyase followed by photoreactivation after UVB reduced the apoptosis rate significantly, whereas empty liposomes had no effect. Likewise, photoreactivating treatment did not affect apoptosis induced by the ligand of CD95, CD95L. UVB exposure at 4 degrees C, which prevents CD95 clustering, also reduced the apoptosis rate, but to a lesser extent. When cells were exposed to UVB at 4 degrees C and treated with photolyase plus photoreactivating light, UVB-induced apoptosis was almost completely prevented. Inhibition of caspase-3, a downstream protease in the CD95 signaling pathway, blocked both CD95L and UVB-induced apoptosis, whereas blockage of caspase-8, the most proximal caspase, inhibited CD95L-mediated apoptosis completely, but UVB-induced apoptosis only partially. Although according to these data nuclear effects seem to be slightly more effective in mediating UVB-induced apoptosis than membrane events, both are necessary for the complete apoptotic response. Thus, this study shows that nuclear and membrane effects are not mutually exclusive and that both components contribute independently to a complete response to UVB.

Antigens, CD↗
PubMed1999

Singlet oxygen mediates the UVA-induced generation of the photoaging-associated mitochondrial common deletion.

Mutations of mitochondrial (mt) DNA accumulate during normal aging. The most frequent mutation is a 4,977-base pair deletion also called the common deletion, which is increased in photoaged skin. Oxidative stress may play a major role in the generation of large scale mtDNA deletions, but direct proof for this has been elusive. We therefore assessed whether the common deletion can be generated in vitro through UV irradiation and whether reactive oxygen species are involved in this process. Normal human fibroblasts were repetitively exposed to sublethal doses of UVA radiation and assayed for the common deletion employing a semiquantitative polymerase chain reaction technique. There was a time/dose-dependent generation of the common deletion, attributable to the generation of singlet oxygen, since the common deletion was diminished when irradiating in the presence of singlet oxygen quenchers, but increased when enhancing singlet oxygen half-life by deuterium oxide. The induction of the common deletion by UVA irradiation was mimicked by treatment of unirradiated cells with singlet oxygen produced by the thermodecomposition of an endoperoxide. These studies provide evidence for the involvement of reactive oxygen species in the generation of aging-associated mtDNA lesions in human cells and indicate a previously unrecognized role of singlet oxygen in photoaging of human skin.

Cell Survival↗
PubMed1999

Nitric oxide fully protects against UVA-induced apoptosis in tight correlation with Bcl-2 up-regulation.

A variety of toxic and modulating events induced by UVA exposure are described to cause cell death via apoptosis. Recently, we found that UV irradiation of human skin leads to inducible nitric-oxide synthase (iNOS) expression in keratinocytes and endothelial cells (ECs). We have now searched for the role of iNOS expression and nitric oxide (NO) synthesis in UVA-induced apoptosis as detected by DNA-specific fluorochrome labeling and in DNA fragmentation visualized by in situ nick translation in ECs. Activation with proinflammatory cytokines 24 h before UVA exposure leading to iNOS expression and endogenous NO synthesis fully protects ECs from the onset of apoptosis. This protection was completely abolished in the presence of the iNOS inhibitor L-N5-(1-iminoethyl)-ornithine (0.25 mM). Additionally, preincubation of cells with the NO donor (Z)-1-[N(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-i um-1, 2-diolate at concentrations from 10 to 1000 microM as an exogenous NO-generating source before UVA irradiation led to a dose-dependent inhibition of both DNA strand breaks and apoptosis. In search of the molecular mechanism responsible for the protective effect, we find that protection from UVA-induced apoptosis is tightly correlated with NO-mediated increases in Bcl-2 expression and a concomitant inhibition of UVA-induced overexpression of Bax protein. In conclusion, we present evidence for a protective role of iNOS-derived NO in skin biology, because NO either endogenously produced or exogenously applied fully protects against UVA-induced cell damage and death. We also show that the NO-mediated expression modulation of proteins of the Bcl-2 family, an event upstream of caspase activation, appears to be the molecular mechanism underlying this protection.

Animals↗
PubMed1999

[Periorbital edema as the initial symptom of lupus erythematosus profundus. Case report and discussion of the literature].

Periorbital edema may occur initially or in the course of a wide variety of diseases. One of these diseases is lupus panniculitis, a variant of lupus erythematosus, characterized by firm subcutaneous nodules that may ulcerate with subsequent scar formation. We present a case of lupus panniculitis in which the periorbital edema was the initial manifestation. Knowledge about the differential diagnostic possibilities of periorbital edema as well as the different variants of cutaneous lupus erythematosus is important to reach the correct diagnosis.

Diagnosis, Differential↗
PubMed1999

Ultraviolet A1 (340-400 nm) phototherapy for cutaneous T-cell lymphoma.

BACKGROUND: The results of a recent study suggested that ultraviolet A1 radiation (UVA1R; 340-400 nm) phototherapy for atopic dermatitis works through induction of apoptosis in skin-infiltrating helper T cells, indicating the possibility that other helper T cell-mediated skin diseases may respond to UVA1R as well. OBJECTIVE: The purpose of this open pilot study was to assess the therapeutic effectiveness of UVA1 phototherapy for cutaneous T-cell lymphoma (CTCL). METHODS: UVA1 phototherapy was used as monotherapy in patients (n = 3) with histologically proven CTCL (stages IA and IB). For daily whole body UVA1 irradiations, either a high-dose (n = 2; 130 J/cm2 UVA1 per exposure) or medium-dose (n = 1; 60 J/cm2 UVA1) regimen was used. Therapeutic effectiveness was assessed clinically and histologically. RESULTS: In each of the 3 patients, skin lesions began to resolve after only a few UVA1 radiation exposures. Complete clearance was observed between 16 and 20 exposures, regardless of whether the high- or medium-dose regimen had been employed. CONCLUSION: These studies suggest that patients with CTCL stages IA and IB can be treated effectively with UVA1 phototherapy.

Aged↗
PubMed1999

Mechanisms of ultraviolet (UV) B and UVA phototherapy.

Ultraviolet (UV) radiation has been used for decades with great success and at a constantly increasing rate in the management of skin diseases, becoming an essential part of modern dermatologic therapy (Krutmann et al, 1999). For phototherapy, irradiation devices emitting either predominantly middlewave UV (UVB, 290-315 nm) or longwave UV (UVA, 315-400 nm) radiation are employed. In former years, patients were treated with broad-band UVB, broad-band UVA, or combination regimens. Broad-band UV phototherapy, however, is being replaced more frequently by the use of irradiation devices that allow treatment of patients' skin with selected emission spectra. Two such modalities which have their origin in European Photodermatology are 311 nm UVB phototherapy (which uses long-wave UVB radiation above 300 nm rather than broadband UVB) and high-dose UVA1 therapy (which selective employs long-wave UVA radiation above 340 nm). In Europe, 311 nm UVB phototherapy has almost replaced classical broad-band UVB phototherapy and has significantly improved therapeutic efficacy and safety of UVB phototherapy (van Welden et al, 1988; Krutmann et al, 1999). The constantly increasing use of UVA-1 phototherapy has not only improved UVA phototherapy for established indications such as atopic dermatitis (Krutmann et al, 1992a, 1998; Krutmann, 1996), but has also provided dermatologists with the opportunity to successfully treat previously untractable skin diseases, e.g., connective tissue diseases (Stege et al, 1997; Krutmann, 1997). These clinical developments have stimulated studies about the mechanisms by which UVB and UVA phototherapy work. The knowledge obtained from this work is an indispensable prerequisite to make treatment decisions on a rationale rather than an empirical basis. Modern dermatologic phototherapy has started to profit from this knowledge, and it is very likely that this development will continue and provide dermatologists with improved phototherapeutic modalities and regimens for established and new indications. This review aims to provide an overview about current concepts of the mode of action of dermatologic phototherapy. Special emphasis will be given on studies that have identified previously unrecognized immunosuppressive/anti-inflammatory principles of UV phototherapy.

Animals↗
PubMed1998

Successful use of extracorporeal photochemotherapy in the treatment of severe acute and chronic graft-versus-host disease.

Extracorporeal exposure of peripheral blood mononuclear cells to the photosensitizing compound 8-methoxypsoralen and ultraviolet A radiation has been shown to be effective in the treatment of several T-cell-mediated diseases, including cutaneous T-cell lymphoma and rejection after organ transplantation. We present 21 patients (10 men and 11 women) with hematological malignancies with a median age of 36 years (range, 25 to 55 years) who had received marrow grafts from sibling (n = 12) or unrelated (n = 9) donors. Six patients had acute graft-versus-host disease (GVHD) grade II to III not responding to cyclosporine A (CSA) and prednisolone when referred to extracorporeal photochemotherapy (ECP). In 15 patients, 2 to 24 months after bone marrow transplantation (BMT), extensive chronic GVHD with involvement of skin (n = 15), liver (n = 10), oral mucosa (n = 11), ocular glands (n = 6), and thrombocytopenia (n = 3) developed and was unresponsive to conventional therapy, including steroids. All patients were treated with ECP on 2 consecutive days every 2 weeks for the first 3 months and thereafter every 4 weeks until resolution of GVHD. ECP was tolerated excellently without any significant side effects. After a median of 14 cycles of ECP, acute GVHD resolved completely in 4 of 6 patients (67%) and partially in another 2 patients. Cutaneous chronic GVHD completely resolved in 12 of 15 (80%) patients. Contractures of knees and elbows due to scleroderma resolved partially. Oral mucosal ulcerations resolved in all patients. Seven of 10 patients (70%) with liver involvement had complete responses after ECP. After discontinuation of ECP, no severe infections were observed. Our findings suggest that ECP is a safe and effective adjunct therapy for both acute and extensive chronic GVHD with skin and visceral involvement and resistance to conventional therapy.

Acute Disease↗
PubMed1998

Therapeutic photoimmunology: photoimmunological mechanisms in photo(chemo)therapy.

Ultraviolet radiation, either alone or in combination with photosensitizing agents, is widely used for the treatment of skin diseases. The efficacy of photo- and photochemotherapeutic modalities is thought to result, at least in part, from the induction of immunomodulatory effects. In particular, UV radiation has been shown to affect (i) the production of soluble mediators, (ii) the expression of cell-surface receptors and (iii) to induce apoptosis in pathogenetically relevant cells. UVB radiation-induced immunomodulatory effects are limited to the epidermis, whereas UVA radiation affects both epidermal and dermal cell populations. UVB and UVA radiation can exert essentially identical immunomodulatory effects, which result, however, from different photobiological mechanisms.

Animals↗
PubMed1998

Human eosinophils produce biologically active IL-12: implications for control of T cell responses.

The present study assessed the capacity of eosinophils (EOS) to synthesize the cytokine IL-12. Blood-derived, highly purified human EOS from six atopic patients and two nonatopic individuals were treated in culture with IL-4, IL-5, granulocyte-macrophage CSF, IFN-gamma, TNF-alpha, IL-1alpha, RANTES, and complement 5a, respectively. The expression of both IL-12 protein and mRNAs for the p35 and p40 IL-12 subunits was strongly induced in all donors by the Th2-like cytokines IL-4 and granulocyte-macrophage CSF and was also moderately induced by TNF-alpha and IL-1alpha. IL-5 treatment resulted in IL-12 synthesis in four atopic donors and one nonatopic donor, whereas IFN-gamma induced IL-12 synthesis in only two atopic donors. In contrast, RANTES exclusively induced mRNA for the p40 subunit without detectable protein release, and complement 5a had no effect on IL-12 mRNA or protein expression. EOS-derived IL-12 was biologically active, because supernatants derived from IL-4-treated EOS superinduced the Con A-induced expression of IFN-gamma by a human Th1-like T cell line. This activity was neutralized by anti-IL-12 Abs. In conclusion, EOS secrete biologically active IL-12 after treatment with selected cytokines, which mainly represent the Th2-like type. Consequently, EOS may promote a switch from Th2-like to Th1-like immune responses in atopic and parasitic diseases.

Cell Line↗
PubMed1998

[Extracorporeal photopheresis in therapy-refractory disseminated discoid lupus erythematosus].

Lupus erythematosus (LE) is a disease with a wide spectrum of cutaneous and systemic manifestations. Discoid LE (DLE) is the most common form of cutaneous LE; the disseminated form of DLE is rare. We report an encouraging response to treatment with extracorporeal photopheresis (ECP) in a single patient with disseminated DLE who did not respond to conventional therapy. To the best of our knowledge this is the first successful use of ECP in the management of such a patient. Extracorporeal photopheresis is a therapeutic modality that has been under investigation for more than 12 years. Although originally developed for the treatment of cutaneous T-cell lymphoma, ECP has recently been used for the management of autoimmune diseases including systemic scleroderma, pemphigus vulgaris and SLE, as well as prevent organ rejection in patients with cardiac or kidney transplants and graft versus host disease after bone marrow transplantation.

Dose-Response Relationship, Drug↗