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Biomedical subjects

T Ruzicka

Publications and source records attributed to T Ruzicka.

At least 343 records · Page 19Linked to original sources
PubMed1987

Benign symmetric lipomatosis Launois-Bensaude. Report of ten cases and review of the literature.

Benign symmetric lipomatosis Launois-Bensaude is a disease rarely reported in the American literature and not mentioned in the standard English textbooks of dermatology. It seems, however, to be relatively common in Europe. Between 1981 and 1985 we examined twelve patients, and a number of case reports have been published in French and German literature. We describe ten typical cases and review the literature. The disease is characterized by massive symmetric fat deposits predominantly in the neck and shoulder girdle area. Pathogenetically, the increase in fatty tissue is assumed to result from a localized defect in catecholamine-induced lipolysis. The disease is frequently associated with alcoholism, hepatopathy, glucose intolerance, hyperuricemia, and malignant tumors of the upper airways, requiring thorough clinical evaluation of all patients. Dietary treatment and weight loss are of limited value in the management of benign symmetric lipomatosis. Surgical removal of lipomatous tissue is frequently followed by recurrence and should be restricted to decompression in patients with functional impairment.

Adult↗
PubMed1987

Effects of chronic intracutaneous administration of arachidonic acid and its metabolites. Induction of leukocytoclastic vasculitis by leukotriene B4 and 12-hydroxyeicosatetraenoic acid and its prevention by prostaglandin E2.

Despite the postulated role of arachidonic acid-derived metabolites in the pathophysiology of chronic inflammatory dermatoses such as psoriasis and atopic or contact dermatitis, the cutaneous effects of their chronic application have not yet been investigated. We therefore studied systematically the effects of chronic intracutaneous administration of arachidonic acid, prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and 12-hydroxyeicosatetraenoic acid (12-HETE) in guinea pigs, and describe previously unrecognized findings partly different from those reported in the past for short-term or topical application of these inflammatory mediators. Leukotriene B4 and 12-HETE led to massive histologic changes characteristic of leukocytoclastic vasculitis. These changes could be prevented by concomitant PGE2 administration. In epidermis, LTB4 and 12-HETE caused some spongiosis as well as hyperplasia and increased tritiated thymidine autoradiographic labeling index. Arachidonic acid and PGE2 alone had little effect. These data suggest that in addition to other inflammatory or hyperproliferative dermatoses, arachidonic acid metabolites formed via lipoxygenase pathways could play a major role in leukocytoclastic vasculitis, whereas PGs could exert a tissue-protective effect.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1987

Nonsteroidal antiinflammatory drugs induce UV-dependent histamine and leukotriene release from peripheral human leukocytes.

The effect of UV-A radiation on the in vitro release of vasoactive mediators from human peripheral leukocytes incubated with different nonsteroidal antiinflammatory drugs (NSAIDs) was studied in the newly developed photo basophil histamine release test (PBHRT). Washed peripheral leukocytes were incubated with 10(-6) to 10(-3) M of various NSAIDs and exposed to 1-100 J/cm2 UV-A. Maximum histamine release was 4% with acetylsalicylic acid, 10% with benoxaprofen, 20% with thiophene, 28% with diclofenac, 39% with tiaprofenic acid, 40% with carprofen, 55% with ketoprofen and not demonstrable with indoprofen. Maximal reactions occurred at UV-A doses of 25 or 50 J/cm2. Leukotriene B4 (LTB4) generation in the supernatants of cells treated with UV-A or NSAID alone was below or close to the detection limit (145 pg/ml). On the contrary, UV-A irradiation of cells incubated with NSAID led to marked LTB4 generation (up to 1,000 pg/ml). The results indicate that many NSAIDs can induce photosensitization in vitro, the PBHRT being a promising new method for identification of possibly phototoxic compounds. Release of vasoactive mediators like histamine or leukotrienes may be involved in the in vivo development of phototoxic or photoallergic side reactions.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1987

Phototoxicity of non-steroidal anti-inflammatory drugs demonstrated in vitro by a photo-basophil-histamine-release test.

The phototoxic activity of the non-steroidal anti-inflammatory drugs (NSAID) acetylsalicylic acid, benoxaprofen, carprofen, diclofenac, indoprofen, ketoprofen, tiaprofenic acid, and of thiophene, a heterocyclic ring structure of the tiaprofenic acid molecule, was evaluated in vitro by a newly developed photo-basophil-histamine-release test (PBHRT) performed with human leukocytes. Cell suspensions incubated with 10(-6) to 10(-3) M of the test compounds were exposed to 1 to 100 J/cm2 UVA. Maximum photo-basophil-histamine-release was 4% with acetylsalicylic acid, 10% with benoxaprofen, 20% with thiophene, 28% with diclofenac, 39% with tiaprofenic acid, 40% with carprofen, 55% with ketoprofen, and not demonstrable with indoprofen. These results indicate that many NSAID can exert phototoxic effects, thus confirming clinical observations as well as other in vitro experiments. The PBHRT seems to be a promising new method for the identification of phototoxic compounds.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1987

Enhanced releasability of prostaglandin E2 and leukotrienes B4 and C4 from leukocytes of patients with atopic eczema.

The releasability of arachidonic acid-derived inflammatory mediators (eicosanoids) from peripheral blood leukocytes has been tested in patients with atopic eczema and healthy, non-atopic controls. Spontaneous and stimulated release of prostaglandin E2 (PGE2), leukotriene B4 (LTB4) and leukotriene C4 (LTC4) has been measured after challenge of cells with various concentrations of anti-IgE, Ca-ionophore A23187 and C5a. The maximal stimulation of cells with Ca-ionophore resulted in the generation of high amounts of all eicosanoids, which was essentially equal in both atopic and control groups. On the other hand, enhanced spontaneous and stimulated eicosanoid release was noted after immunological challenge using C5a and anti-IgE in the atopic eczema group. Thus, our data support the hypothesis of enhanced releasability of inflammatory mediators in atopic eczema.

Adolescent↗
PubMed1987

[Psoriasis pustulosa generalisata--classification, clinical aspects and therapy. Review and experiences with 18 patients].

On the basis of clinico-morphological criteria we suggest the following classification of various pustular forms of psoriasis into four subtypes: generalized pustular psoriasis (von Zumbusch) and its atypical forms, erythema anulare centrifugum-like psoriasis with and without pustulation (EACP); psoriasis vulgaris with pustulation; palmo-plantar pustular psoriasis (Königsbeck-Barber) and its acral variant; acrodermatitis continua suppurativa (Hallopeau), and transitional forms. This classification takes into consideration both clinical aspects and response to treatment, and allows a prognosis of the various types of pustular psoriasis. Owing to its mild course and good treatment results, EACP represents a special form of psoriasis pustulosa generalisata. In our group of patients, systemic glucocorticosteroid therapy has proved deleterious, whereas oral photochemotherapy and etretinate have been found to be highly effective modes of therapy with only mild side effects and have been able to induce even permanent remission in EACP.

Adult↗
PubMed1987

[Erosive pustulous dermatitis of the scalp].

We present a 46-year-old female patient suffering from progressive, pustular and erosive lesions of the scalp. The nosology and the differential diagnosis of this disease entity, called erosive pustular dermatosis of the scalp, are discussed.

Alopecia↗
PubMed1987

[Nutrition and atopic eczema].

Food incompatibility plays a minor role, especially in the case of adult patients, in the complex, multifactorial genesis of the atopic eczema. For approximately 10% of the cases of atopic eczema in children further forms of therapy, including dietary measures, should be considered, apart from the basic therapy according to standard dermatological rules. With this in mind, a test by means of an elimination diet is recommended (elimination of eggs, chicken, milk and possibly colourings and preservatives, citrus fruit, tomatoes, fish and nuts). Due to the difficulty in dietary treatment pharmacological prevention of food allergy (Colimmune) is of theoretical importance. Recently interest has been concentrated on possible roles of lipid mediators in atopic eczema. Leukotriene B4, found in the skin of eczema patients in increased concentration, has been proved to be a mediator. At the moment pilot studies are being carried out on the influence of mediator metabolism by dietary measures.

Allergens↗
PubMed1986

Skin levels of arachidonic acid-derived inflammatory mediators and histamine in atopic dermatitis and psoriasis.

Since the biochemical events leading to cutaneous inflammation in atopic dermatitis and psoriasis are unknown, we studied the levels of arachidonic acid-derived mediators of inflammation as well as histamine in the suction blister fluid obtained from lesional and nonlesional skin of patients with these dermatoses. Mediator levels were determined radioimmunologically. Skin from healthy controls and uninvolved skin from patients contained very low or unmeasurable levels of the 5-lipoxygenase metabolite of arachidonic acid, leukotriene (LT) B4. In contrast, higher levels of LTB4-like immunoreactivity were detected in suction blister fluid from lesional atopic dermatitis skin, and even higher concentrations occurred in psoriasis lesions. LTB4-like immunoreactivity from atopic dermatitis suction blister fluid cochromatographed on reverse-phase high-pressure liquid chromatography with authentic LTB4, thus excluding cross-reaction of the LTB4-antibody with arachidonic acid or monohydroxyeicosatetraenoic acids. In contrast, suction blister concentrations of the cyclooxygenase metabolite of arachidonic acid prostaglandin (PG) E2 showed no significant differences between lesional and nonlesional patient skin and healthy control skin. PGD2 determined as a stable metabolite could not be detected in these samples. Histamine concentrations in lesional skin were within normal range. The elevated levels of the potent proinflammatory and immunomodulating mediator LTB4 could be involved in the pathogenesis of cutaneous inflammation in atopic dermatitis and psoriasis. In addition, they might explain the therapeutic efficiency of glucocorticosteroids, which among other actions inhibit the release of arachidonic acid from phospholipid stores by blocking the enzyme phospholipase A2. However, the specificity of disease expression in atopic dermatitis and psoriasis must be due to factors other than cutaneous LTB4 elevation.

Adolescent↗
PubMed1986

Treatment of hyperhidrosis by a battery-operated iontophoretic device.

A new iontophoretic device was utilized in the treatment of hyperhidrosis axillaris (5 patients), hyperhidrosis manuum (12 patients) and hyperhidrosis pedum (10 patients). Unilateral treatment was carried out daily for 3 weeks. Degree of sweat inhibition was assessed quantitatively in relation to the untreated control side by means of hygrometry and also estimated by a colorimetric method. In 3 patients with palmar hyperhidrosis and in 2 patients with plantar hyperhidrosis sweating returned to normal levels, thus hyperhidrosis was completely curbed. A moderate reduction of sweat rates was induced in 4 patients on palms and in 3 patients on soles. In the remaining group sweat inhibition was only slight. In treatment of palmo-plantar hyperhidrosis side effects were minimal. Axillary hyperhidrosis was only moderately reduced in some patients. Skin irritation due to iontophoresis posed a problem.

Adolescent↗
PubMed1985

Epidermal synthesis and expression of HLA-DR on keratinocytes in lupus erythematosus.

It has been suggested that aberrant expression of HLA-DR plays an important role in the induction of an autoimmune reaction. In lupus erythematosus (LE), skin represents a major target for autoimmune attack. We therefore tested lesional and nonlesional skin from 11 patients with different clinical subtypes of LE for the presence of HLA-DR molecules on keratinocytes using a monoclonal antibody against a non-polymorphic HLA-DR determinant. In all lesions tested, HLA-DR-positive keratinocytes were present, whereas in nonlesional skin, these cells remained HLA-DR negative. To exclude the possibility of passive absorption of DR molecules, the de novo synthesis of HLA-DR was demonstrated by the presence of cytoplasmic HLA-DR gamma chains in keratinocytes. If aberrant HLA-DR expression is a primary event, it could facilitate the recognition of autoantigens on keratinocytes by immunocompetent cells. Alternatively, the synthesis of DR molecules could be induced as a secondary event by mediators derived from the inflammatory infiltrate.

Adult↗
PubMed1985

Polymorphonuclear leukocyte 5-lipoxygenase activity in psoriasis.

5-lipoxygenase-derived products of arachidonic acid are implicated in the pathophysiology of psoriasis, a common hyperproliferative and inflammatory skin disease. We therefore examined whether there is an activation of this enzymatic pathway in extracutaneous tissues. For this purpose, we measured the conversion of 14C-arachidonic acid by polymorphonuclear leukocytes from psoriatic patients and controls. No significant difference in the generation of leukotriene B4 and 5-hydroxyeicosatetraenoic acid by polymorphonuclear leukocytes was noted between the two groups. We conclude that in psoriasis there is no enhanced activity of the 5-lipoxygenase pathway in circulating polymorphonuclear leukocytes.

Adult↗
PubMed1985

Bullous amyloidosis.

A patient with a 12-year history of a relapsing bullous dermatosis is presented. Unusual clinical features included urticarial erythema, conspicuous mottled hyper- and depigmentation, lichenification and ichthyosiform hyperkeratosis. Serum immunoglobulin E levels were elevated. Histological examination showing deposits of amyloid in the uppermost dermis confirmed the diagnosis of bullous amyloidosis. Ultrastructurally, blister formation occurred at the level of the lamina lucida. The amyloid did not react with a panel of antibodies directed against amyloid fibril proteins. No underlying systemic disease was found. The bullous eruption responded to prednisolone therapy.

Amyloid↗
PubMed1985

Treatment of cutaneous lupus erythematosus with etretinate.

Nineteen patients with different clinical subsets of cutaneous lupus erythematosus (LE) were treated with the aromatic retinoid etretinate. In 11 of them excellent or good treatment results were obtained within two to six weeks. Best response to etretinate therapy was seen in male patients with discoid lupus erythematosus. Etretinate should prove a valuable drug in LE therapy.

Adult↗