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Biomedical subjects

N Hunzelmann

Publications and source records attributed to N Hunzelmann.

At least 19 recordsLinked to original sources

[Werner's syndrome].

HISTORY AND CLINICAL FINDINGS: A 49-year-old man of German parentage with Werner's syndrome (including insulin-dependent type 2 diabetes mellitus) was treated in our department for extensive ulcers on his lower legs. GENETICS: Genetic analysis detected a novel compound heterozygous defect (1396delA and 2334delAC) of the WRN gene. TREATMENT AND FURTHER COURSE: The ulcer clearly decreased in size on local and antibiotic treatment as well as autologous fibroplast transplantation. The most severely affected right small finger required amputation with exarticulation. The severe pain caused by the ulcer was successfully treated with temporary blockage of the stellate ganglion and permanent sympathetic blockage at the level of the 2nd thoracic and lumbar vertebrae. CONCLUSION: Werner's syndrome is a rare form of progeria with an autosomal recessive mode of inheritance mimicking the symptoms of accelerated aging. The reduced life expectancy is caused by the increased incidence and early onset of atherosclerosis and malignant tumors. The detection of underlying molecular mechanisms will have an important impact in the field of anti-aging research.

Amputation, Surgical↗

IgE-mediated anaphylactic reaction to purified and recombinant factor VIII in a patient with severe haemophilia A.

We report a 51-year-old patient with severe haemophilia A developing a severe life-threatening anaphylactic reaction to recombinant factor VIII (rFVIII). Anaphylactic reactions are a rare but well-known side effect of FVIII products. The nature of these reactions could not be clarified as previous studies failed to demonstrate a specific IgE response. Here, we could prove a grade 3 anaphlyactic reaction as an IgE-mediated response to rFVIII for the first time by Western blotting.

Anaphylaxis↗

[Pulmonary arterial hypertension in collagen disease: experiences of the German Network for Systemic Scleroderma].

The German Network for Systemic Scleroderma (Deutsches Netzwerk Für Systemische Sklerodermie [DNSS]) has as its aim to improve and standardize the diagnosis and treatment of this rare disease. 14.6 % of patients in the DNSS register have been shown to have pulmonary hypertension (PHT). Comparable international data range from 12 % to 26.7 %. The DNSS recommends annual echocardiography for patients with scleroderma and right-heart catheterization if the systolic pulmonary arterial pressure is higher than 35 mmHg. Aggressive immunosuppressive treatment--in the first instance with cyclophosphamide--should be given only if there is also progressive fibrosis. Drugs that lower the level of PHT also have a favourable effect on other signs of scleroderma.

Catheterization, Swan-Ganz↗

[Current pathophysiological aspects of systemic sclerosis].

Systemic scleroderma is characterized by a chronic inflammatory process of unknown etiology resulting in an increased deposition of connective tissue proteins in the involved organs. Involvement of the vascular system and the resulting fibrosis lead to atrophy and malfunction of the involved internal organs and the skin. Due to the development of new therapeutic concepts in particular with regard to the vascular involvement, the interaction between the vascular system and the connective tissue moves increasingly into focus. This review describes the major advancemades during recent years for the understanding of the pathophysiology of systemic scleroderma.

Animals↗

Phototherapy: a promising treatment option for skin sclerosis in scleroderma?

In systemic sclerosis (SSc; scleroderma) fibrosis of the skin can lead to considerable morbidity. No significant improvement has been reported from studies investigating antifibrotic therapies so far. In dermatology, phototherapy with ultraviolet (UV) irradiation is successfully used for treatment of several diseases because of its anti-inflammatory as well as immunosuppressive mechanisms, and its low-risk profile. In addition, the UVA spectrum in particular exerts antifibrotic effects as it leads to reduction of procollagen synthesis and expression of collagenase-1 in vitro. Accordingly, treatment with long-wavelength UVA-1 irradiation or photochemotherapy with UVA plus the photosensitizer psoralen (PUVA) have been successfully used to reduce skin fibrosis in localized scleroderma (morphea). There are only in particular few reports on treatment of skin sclerosis in SSc, but the results are in concordance with the good experience that have been observed at our and other dermatological centres. Phototherapy is able to stop or inhibit the fibrotic processes and to induce softening of sclerotic skin, especially in limited SSc. Phototherapy thus represents a therapeutic alternative for antifibrotic treatment with a low rate of adverse effects, which should be applied before the sclerotic process has proceeded too far.

Fibrosis↗

Rituximab in refractory autoimmune bullous diseases.

Treatment of autoimmune blistering diseases consists of systemic glucocorticosteroids usually in combination with additional immunosuppressants such as azathioprine and mycophenolate mofetil or immunomodulators such as dapsone, antibiotics, intravenous immunoglobulins, and immunoadsorption. In some patients, these treatment regimens are not sufficient to control disease activity and/or lead to intolerable adverse events. Rituximab, originally developed for the treatment of non-Hodgkin's lymphoma, is an anti-CD20 humanized monoclonal antibody leading to transitory B-cell depletion. For this indication, rituximab is widely employed, and severe side-effects rarely observed. Subsequently, the B-cell-depleting effect of rituximab has been exploited successfully in various autoimmune disorders, including autoimmune blistering diseases. Here, we review the effect of rituximab in such diseases. To date, application of rituximab has been reported in 26 treatment-resistant patients with the vulgaris, foliaceus, and paraneoplastic variants of pemphigus as well as in bullous pemphigoid and epidermolysis bullosa acquisita. All but a single patient showed clinical improvement with reduction of lesion formation. In about a third, a clinical remission requiring further immunsuppressive medication was achieved, and in about a quarter, complete remission was induced. In addition, the mode of action and adverse events of rituximab as well as adjuvant immunosuppressive treatments, and the effect on levels of circulating autoantibodies in these patients are discussed.

Antibodies, Monoclonal↗

Interleukin 4 and prolonged hypoxia induce a higher gene expression of lysyl hydroxylase 2 and an altered cross-link pattern: important pathogenetic steps in early and late stage of systemic scleroderma?

The major pathological processes of systemic scleroderma (SSc) comprise inflammation and microvascular damage in the early or acute progressive stage as well as tissue fibrosis and hypoxia in the chronic end stage. Fibrosis seems to be a general phenomenon characterized by an increase of hydroxylysine aldehyde derived collagen cross-links which has been shown in vitro for systemic scleroderma fibroblasts. In the present study, we analyzed the cross-link pattern and the gene expression of lysyl hydroxylase 2 (LH2) in the skin of SSc. Furthermore, we determined the modulatory impact of inflammatory cytokines (interleukin 4, TNF- alphaand interleukin 1alpha/beta) and prolonged hypoxia on the cross-link profile and the gene expression of LH2, respectively. The concentration of hydroxylysine aldehyde derived cross-links was significantly increased in SSc, while the level of lysine aldehyde derived cross-links was not changed. Accordingly, a marked increase of the transcriptional level of LH2 was found. In long term dermal fibroblast cultures, only interleukin 4 induced an increase of hydroxylysine aldehyde derived cross-links accompanied by a higher gene expression of LH2. Furthermore, prolonged hypoxia induced a marked increase of the mRNA level of LH2 in relation to collagen I. The skin of SSc is characterized by an increase of the transcriptional activity of LH2 leading to an altered cross-link pattern. The changes in the quality of the collagenous matrix can also be obtained in cell culture by the exposure of fibroblasts to interleukin 4 or prolonged hypoxia emphasizing the role of this mediator in the acute and the low oxygen tension in the chronic phase of the disease.

Cell Hypoxia↗

Keratoacanthoma centrifugum marginatum accompanied by extensive granulomatous foreign body reaction.

We describe a 58-year-old woman with a 4-year history of papular lesions with a partly verruciform appearance on the eyelids and the adjacent areas of the nose. The lesions progressed slowly but constantly into the surrounding areas with central scarring. Histopathology showed epidermal endophytic proliferations under a pronounced hyperparakeratosis. In the adjacent dermis a lymphohistiocytic infiltrate with giant cells of the foreign-body-reaction type was seen in close contact to extracellular keratin deposits. Although some cytopathological signs typical for viropathic effects were observed, no human papilloma virus-DNA was detected within the lesions by polymerase chain reaction. According to the histological picture and the clinical course we diagnosed a keratoacanthoma centrifugum marginatum. We present this case because of the strong granulomatous foreign body reaction which might complicate the diagnosis and has not been described for this keratoacanthoma variant so far.

Facial Dermatoses↗

[PM-Scl antibody positive systemic sclerosis associated with inclusion-body myositis].

We describe a 72- year-old patient with a ten year history of anti-PM-Scl positive systemic sclerosis associated with inclusion-body myositis. While the association of dermatomyositis and polymyositis with anti-PM-Scl positive systemic sclerosis is frequently reported, inclusion-body myositis was, to the best of our knowledge, only previously described once in association with anti-PM-Scl-positive systemic sclerosis. The distinction between inclusion-body myositis and other forms of inflammatory myopathy, like the histopathologically well distinguishable polymyositis or dermatomyositis, is relevant because of the poor response of inclusion- body myositis to immunosuppressive treatment. Our case underlines that in patients with anti-PM-Scl-positive systemic sclerosis and treatment resistant progressive myopathy the diagnosis of inclusion body myositis should be considered.

Aged↗

A novel compound heterozygous mutation in Werner syndrome results in WRN transcript decay.

BACKGROUND: Werner syndrome (WS) is a rare autosomal recessive progeroid disorder caused by mutations of the WRN gene encoding a protein of the RecQ-type family of DNA helicases. OBJECTIVES: To develop a rapid and simple reverse transcription-polymerase chain reaction (RT-PCR) strategy for mutation analysis of the WRN gene, to identify pathogenic mutations in a German patient with WS and to determine the effects of the pathogenic mutations on WRN mRNA stability. METHODS: Allele-specific RT-PCR, semiquantitative RT-PCR, DNA sequencing. RESULTS: We describe a novel and rapid RT-PCR-based method for mutation analysis in WS and report a German patient with WS carrying a previously reported (1396delA) as well as a novel nonsense mutation (2334delAC) of the WRN gene. By semiquantitative RT-PCR analysis we demonstrate that this compound heterozygous genotype leads to WRN transcript decay. CONCLUSIONS: In previous studies WS was primarily attributed to a loss of function of stable truncated WRN gene products. Our findings indicate that mutations can also lead to markedly decreased WRN transcript stability.

Base Sequence↗

Anti-CD20 monoclonal antibody (rituximab) in the treatment of pemphigus.

BACKGROUND: Pemphigus is a severe autoimmune blistering disorder caused by autoantibodies to desmoglein 1 and 3. The disease course is typically severe, thus requiring multiple immunosuppressive agents. The treatment is still challenging and in some patients with recalcitrant disease, therapies fail and therapeutic options are limited. OBJECTIVES: To investigate whether depletion of B lymphocytes that are thought to produce disease-causing autoantibodies shows a long-term benefit in pemphigus. METHODS: Five patients diagnosed as having pemphigus vulgaris and pemphigus foliaceus were treated with the monoclonal antibody rituximab. Rituximab was administered intravenously at a dosage of 375 mg m(-2) once weekly for 4 weeks. RESULTS: The treatment was well tolerated and all patients showed a good response over a follow-up period of up to 3 years, allowing immunosuppressive treatment to be reduced or terminated. B-cell depletion persisted for 6-12 months, and in one patient for almost 3 years. CONCLUSIONS: This study highlights the prolonged effect and disease control after one single course of rituximab and further extends the spectrum of treatments of bullous autoimmune disorders.

Adult↗

Association of killer cell immunoglobulin-like receptors with scleroderma.

OBJECTIVE: Scleroderma is an autoimmune disorder of unknown etiology. A genetic contribution has been demonstrated, and genes influencing activation of the immune system have been potentially identified as candidate genes in this process. The repertoire of killer cell immunoglobulin-like receptors (KIRs) that are involved in the activation of T cells and natural killer cells is highly variable. Recently, an association of KIR2DS2 with vasculitis in patients with rheumatoid arthritis has been reported. Because scleroderma is characterized by an involvement of the vascular system, we sought to determine whether KIR2DS2 is associated with scleroderma. METHODS: We typed 9 KIR genes in 102 patients with scleroderma and in 100 blood donors, using polymerase chain reaction on genomic DNA. RESULTS: Twelve patients with scleroderma, compared with only 2 blood donors, had KIR phenotypes characterized by the presence of the activating KIR2DS2 and the absence of the corresponding inactivating KIR2DL2 (P = 0.005). CONCLUSION: The genetic combination of KIR2DS2+ and KIR2DL2- is associated with scleroderma.

Genetic Predisposition to Disease↗

Enhanced frequency of a PTPRC (CD45) exon A mutation (77C-->G) in systemic sclerosis.

A point mutation in exon A (C to G transversion at position 77) of human PTPRC (CD45) has recently been associated with the development of multiple sclerosis (MS) for at least a subgroup of patients. In the present report, we studied the frequency of the 77C-->G transversion in two other autoimmune diseases namely systemic sclerosis (SSc) and systemic lupus erythematosus (SLE). The mutation was found with significantly enhanced frequency in patients suffering from SSc suggesting that PTPRC could play a role as susceptibility gene not only in MS but also in other autoimmune diseases. Further understanding of the mode of interaction of mutant PTPRC with other susceptibility genes may uncover mechanisms common in various autoimmune disorders.

Exons↗