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Biomedical subjects

T Ruzicka

Publications and source records attributed to T Ruzicka.

At least 181 records · Page 10Linked to original sources
PubMed1998

Atopic eczema between rationality and irrationality.

A topic eczema is one of the most common chronic inflammatory skin diseases. Its treatment is a matter of intensive controversy between rational academic medicine and irrational alternative complementary medicine more than any other skin disease. Rational therapy is based on a sound pathophysiological foundation. The complex pathophysiology of the disease includes interactions between genetic predisposition and exogenous provocation factors, and treatment necessitates an integrated holistic approach. Despite excellent therapeutic results with the methods of conventional medicine, which uses mostly drugs of natural origin such as glucocorticosteroids, patients with atopic eczema and their parents frequently seek complementary treatments that use unproven and unvalidated diagnostic and therapeutic procedures. Treatments based on simplistic theories and irrational ideologies cause unnecessary long-term suffering to patients and are harmful because they withhold effective treatment modalities.

Combined Modality Therapy↗
PubMed1998

Photodynamic therapy in dermatology.

Photodynamic therapy (PDT) uses exogenously administered or endogenously formed photosensitizers activated by light to induce cell death via formation of singlet oxygen and other free radicals. Photodynamic therapy is increasingly used for the treatment of skin cancers and other indications. The efficacy of PDT depends on the structure of the photosensitizer, the administration modality, the light source, and the treatment procedure. We reviewed the most recent clinical and experimental developments in PDT research related to dermatology. The substrate under most intense investigation in PDT research is delta-aminolevulinic acid (ALA). Photodynamic therapy with topically applied ALA has been shown to be highly efficient in the treatment of cutaneous neoplasms by using intralesionally formed porphyrins as photosensitizers. For solar keratoses, best response rates have been described. delta-Aminolevulinic-PDT is also efficient in the treatment of superficial basal cell and squamous cell carcinomas. In addition, the fluorescence of ALA-induced porphyrins under a Wood light is highly selective in neoplastic cutaneous tissue and offers a useful technique in detecting and delineating skin tumors with ill-defined borders.

Administration, Cutaneous↗
PubMed1998

Topical tacrolimus is not effective in chronic plaque psoriasis. A pilot study.

BACKGROUND: Cyclosporine for the treatment of psoriasis constitutes a new approach. Alternative systemic cyclosporine derivatives have been studied to find an immunosuppressive drug with fewer adverse effects. Tacrolimus is one of these new immunosuppressive drugs. Systematically, it has been proven effective in treating psoriasis. A topical formulation of tacrolimus is attractive because it has fewer adverse effects and is useful for a large group of patients. We report for the first time on the efficacy of nonocclusive topical tacrolimus in the treatment of psoriasis. OBSERVATIONS: After a washout phase of 2 weeks, patients were randomized to receive 0.005% calcipotriol ointment twice daily, placebo ointment once daily, or 0.3% tacrolimus ointment once daily. One psoriatic plaque was treated with a surface area of 40 to 200 cm2. Efficacy was estimated using the local psoriasis severity index. The reduction in the local psoriasis severity index score after 6 weeks was 62.5% in the calcipotriol group, 33.3% in the tacrolimus group, and 42.9% in the placebo group. CONCLUSIONS: There was no statistically significant difference between the efficacy of tacrolimus and placebo ointment (P = .77). Calcipotriol ointment, applied twice daily, had a better effect than tacrolimus ointment and placebo ointment once daily.

Administration, Cutaneous↗
PubMed1998

An integrated model for the differentiation of chemical-induced allergic and irritant skin reactions.

Contact and photocontact allergic as well as irritant and photoirritant skin reactions represent a major problem in clinical dermatology and during the development of new pharmaceuticals. Furthermore, there is a lack of in vitro and in vivo assays that provide a clear differentiation between allergic and irritant skin reactions. Here, we describe an integrated model to differentiate between chemical-induced allergic and irritant skin reactions by measuring objective and easy-to-determine parameters within both skin and skin-draining lymph nodes. Dose-response studies with standard contact and photocontact allergens as well as irritants and photoirritants revealed that irritants predominantly induced skin inflammation, which in turn stimulated draining lymph node cell proliferation. In contrast, the induction phase of contact or photocontact allergy was characterized by marginal skin inflammation, but a marked activation and proliferation of skin-draining lymph node cells. Therefore, a differentiation index (DI) was defined describing the relation between skin-draining lymph node cell activation (lymph node cell count index) and skin inflammation (ear swelling). A DI > 1 indicates an allergic reaction pattern whereas DI < 1 demonstrates an irritant potential of a chemical. Experiments with the contact allergen oxazolone, the photocontact allergen TCSA + UVA, the irritant croton oil, and the photoirritant 8-methoxypsoralen + UVA confirmed the predictive value of DI. Furthermore, flow cytometric analysis of lymph node-derived T- and B-cell subpopulations revealed that contact sensitizer, but not irritant, induced the expression of CD69 on the surface of I-A+ cells. In conclusion, further studies with a broad range of irritants and allergens will be required to confirm general applicability.

Animals↗
PubMed1998

[Psychosomatic disorders in dermatology--incidence and need for added psychosomatic treatment].

In a cooperative study involving the Department of Dermatology and the Department of Psychosomatic Medicine/Psychotherapy of the University of Düsseldorf, 187 patients were evaluated for psychosomatic disease and indenient psychological testing. The distribution of skin diseases and psychosomatic ICD 10 diagnoses are presented. It was found that patient evaluation-(symptom-complaint-questionnaire) and expert evaluation correlate positive. It therefore seems worthwhile examining dermatology in-patient's for psychosomatic problems in order to facilitate combined dermatological and psychosomatic approach not only in the hospital but also during the post-discharge ambulatory treatment.

Adaptation, Psychological↗
PubMed1998

[Scabies--provoked bullous lichen planus in a child].

Lichen ruber planus is considered a T-cell mediated immunologic reaction with unclear pathogenesis. Drugs and infections (especially hepatitis B and C) are well-known provocation factors. After an infection with scabies a 13 year old boy developed a generalized lichen planus including bullous lesions. For the first time scabies is presented as a trigger for lichen planus. In childhood, lichen planus is characterized by atypical clinical features and sometimes a severe course.

Adolescent↗
PubMed1998

Nitric oxide and its implications in skin homeostasis and disease - a review.

The recent identification of the nitric oxide synthase (NOS) pathway in various cell types in the skin has provided important insight into the molecular mechanisms underlying regulatory and homeostatic functions of the skin. Many studies also point to perturbations or defects in the signaling cascade of nitric oxide (NO) and reactive nitrogen intermediates as key players in skin disease pathogenesis. A critical role for NO is now established for a subset of human skin diseases, and new mechanism-based therapies may be available in the near future. This remarkable progress and the implications it may have for common forms of skin disease are reviewed here.

Animals↗
PubMed1998

Defects of mitochondrial respiratory chain in multiple symmetric lipomatosis.

Using lymphocytes from nine unrelated patients with multiple symmetric lipomatosis we investigated a possible defect in the mitochondrial respiratory chain as the biochemical cause for the disease. A significant decrease in oxygen consumption of intact lymphocytes as well as a decreased activity of the individual components of the respiratory chain were detected. These findings are consistent with the recently described deletions and point mutations of mitochondrial DNA in patients suffering from this disease.

Adult↗
PubMed1998

Identification of a soluble interleukin-8 inhibitor in the supernatant of polymorphonuclear leukocytes.

Interleukin-8 (IL-8) plays a crucial role in the pathogenesis of inflammatory and hyperproliferative diseases in various organs. The purpose of the present investigation was to establish whether there is any naturally occurring inhibitor of IL-8. Here we demonstrate that an IL-8 inhibitor (IL-8INH) is present in the supernatant of polymorphonuclear (PMN) leukocytes. The release of IL-8INH could be increased by stimulating the PMN leukocytes by concanavalin A. IL-81NH blocks the IL-8-induced chemotaxis and Candida albicans killing activity of PMN leukocytes and epidermal cells in vitro, and IL-8-induced neutrophil infiltration in the mouse ear in vivo. The mechanism of action of IL-8INH involves blocking of 125I-IL-8 binding to the IL-8 receptor. Binding of 125I-IL-8 to neutrophils could not be displaced by the IL-8INH, however, preincubation of 125I-IL-8 with IL-8INH increased binding inhibition, suggesting an interaction between IL-8 and the inhibitor. Crosslinking of 125I-IL-8 to IL-8INH shows that IL-8INH binds specifically to 125I-IL-8, and the IL-8INH protein has an apparent molecular weight of 52 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The partial purification of the IL-8INH on DEAE-Sephadex anion-exchange chromatography column also suggests a 50-60-kDa inhibitor protein which blocks IL-8-induced effects on neutrophils by binding to IL-8.

Animals↗
PubMed1998

Successful monotherapy of severe and intractable atopic dermatitis by photopheresis.

BACKGROUND: Patients with chronic atopic dermatitis can become unresponsive to standard immunosuppressive therapy and thus pose a serious therapeutic problem. OBJECTIVE: Our purpose was to evaluate the therapeutic effectiveness of photopheresis in the management of patients with severe and intractable atopic dermatitis. METHODS: Photopheresis was used as monotherapy in patients (n = 3) who previously did not respond to treatment with glucocorticosteroids, cyclosporine, phototherapy, or photochemotherapy. Patients were treated at 2-week intervals (total number of treatments = 10). RESULTS: In all patients, photopheresis induced clinical improvement and reduction of elevated serum levels of eosinophil cationic protein and total IgE. Prolongation of the intervals between treatments from 2 to 4 weeks caused worsening in one patient, whereas shortening of treatment-free intervals improved both clinical and laboratory findings. CONCLUSION: These studies indicate that photopheresis may be used as monotherapy for the treatment of patients with severe atopic dermatitis that has become intractable to standard therapeutic modalities.

Adult↗
PubMed1998

Carbon dioxide laser treatment of extramammary Paget's disease guided by photodynamic diagnosis.

Extramammary Paget's disease (EPD) is a rare malignancy occurring mainly in apocrine gland-bearing regions. Surgical excision is the treatment of choice. This may be very difficult or even impossible if the disease is widespread or located in a critical anatomical site. We report on the successful treatment of a 71-year-old man with EPD in the suprapubic region with CO2 laser guided by photodynamic diagnosis.

Aged↗
PubMed1998

Comparison of calcipotriol monotherapy and a combination of calcipotriol and betamethasone valerate after 2 weeks' treatment with calcipotriol in the topical therapy of psoriasis vulgaris: a multicentre, double-blind, randomized study.

A clinical study was conducted to determine whether, in the topical treatment of psoriasis, a combination of calcipotriol and betamethasone valerate after previous treatment with calcipotriol alone was more effective than the continuation of the monotherapy with calcipotriol, especially in 'low responders'. Patients (n = 169) with the clinical diagnosis 'chronic plaque-type psoriasis' were treated twice daily for 2 weeks with calcipotriol, followed by a 4-week treatment with calcipotriol monotherapy in 87 patients or combined calcipotriol/betamethasone valerate in 82 patients; all patients were followed for 8 weeks. The psoriasis area and severity index (PASI) was used to compare the two treatment groups. The overall therapeutic result was also assessed by the investigators and patients. The combination therapy was more effective, as assessed by all evaluated variables; moreover, patients showing insufficient response to calcipotriol alone after 2 weeks showed a regression of psoriatic lesions using the combination regimen. Thus, the combination of calcipotriol and topical steroids is recommended as the therapy of first choice for patients who do not respond well to treatment with 2 weeks of calcipotriol alone. Furthermore, this combination reduces the hazards associated with the long-term use of topical corticosteroids (atrophy and rebound) as well as the irritation associated with calcipotriol.

Adolescent↗