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Biomedical subjects

T Ruzicka

Publications and source records attributed to T Ruzicka.

At least 235 records · Page 13Linked to original sources
PubMed1996

Influence of topical photodynamic therapy with 5-aminolevulinic acid on porphyrin metabolism.

Photodynamic therapy (PDT) with topically applied 5-aminolaevulinic acid (5-ALA) is increasingly used for treating tumours. The efficacy of topical PDT is limited to superficial and initial tumours. The topically applied doses of 5-ALA vary from 0.02 to 7.0 g per session according to the type of lesion. There are no studies on the influence of topically applied 5-ALA on the systemic accumulation of porphyrins or porphyrin precursors. A group of 20 patients with actinic keratoses (AK) and basal cell carcinomas (BCC) were treated by topical PDT with 5-ALA. Prior to and 6 and 24 h after PDT, 5-ALA and total porphyrin concentrations were determined in red blood cells and plasma, respectively. In addition, before and after 5-ALA treatment, 24-h urine samples were collected and porphyrins and porphyrin precursors were measured. There was no significant alteration in porphyrin metabolism. In some patients, a slight but insignificant increase in erythrocyte and plasma porphyrins was found 6 h after 5-ALA PDT. This investigation confirms clearly the safety of this treatment modality and demonstrates that 5-ALA application (up to 7 g) in the course of PDT has no influence on the concentrations of porphyrins and porphyrin precursors measured in various compartments.

Administration, Topical↗
PubMed1996

[Photodynamic therapy and breast-plasty of a extensive superficial trunk skin basalioma of the breast. An effective combination therapy with photodynamic diagnosis].

We treated a large superficial basal cell carcinoma (ca. 10 x 6 cm) on the right breast in a 48-year old woman with photodynamic therapy (PDT). Fractionated PDT was performed by topical application of delta-aminolevulinic acid (delta-ALA, 20%) with subsequent red light (570-750 nm; 180 J/ cm2) in three sessions. Nearly total remission of the tumor resulted; however, a few residual neoplastic islands partly infiltrating the nipple-areola complex could be detected by photodynamic diagnosis (PDD). These fluorescent areas were marked, excised, and the defect was closed by a rotation advancement flap. Total excision of the tumor was verified histologically. By combining PDT and surgery, this large tumor was treated with excellent cosmetic results. This case demonstrates the efficiency of topical PDT with adjunctive plastic surgery controlled by PDD even in large tumors.

Administration, Topical↗
PubMed1996

[Purpura fulminans with extensive skin necroses].

Purpura fulminans must be treated as an emergency in internal medicine and dermatology. Its characteristic features are the sudden development of progressively enlarging haemorrhagic skin necrosis, severe disseminated intravascular coagulation with consumption of anticoagulant factors, and signs of shock. Purpura fulminans can be classified into a neonatal form with inherited protein C deficiency and an acquired type for which multiple causes are known. Clinically it is characterized by massive ecchymosis with haemorrhagic blebs and acral necrosis. Histologically the lesions show widespread extravasation of erythrocytes and thrombosis of small vessels. Thrombocytopenia, decrease of coagulation factors, the presence of fibrinogen split products and fragmented erythrocytes in the blood smear help to confirm the diagnosis. The therapy includes fresh-frozen plasma, heparin, antibiotics and surgical debridement of necrotic areas. It is important to recognize the disease promptly because the mortality rate is about 30-40% and only quick intervention helps to save the life of the patient.

Aged↗
PubMed1996

Is the mismatch repair deficient type of Muir-Torre syndrome confined to mutations in the hMSH2 gene?

The Muir-Torre syndrome (MTS) is a rare autosomal-dominant condition characterized by the occurrence of sebaceous skin lesions and internal tumours in a patient. It has been demonstrated that at least a subgroup of MTS exhibits clinical and molecular genetic features of hereditary nonpolyposis colorectal cancer, including microsatellite instability in skin and visceral tumours, because of mutations in DNA mismatch repair genes. We have identified germline mutations in the hMSH2 gene in two unrelated MTS patients ascertained because of their skin tumours. Our results, together with published MTS cases, support the hypothesis that MTS with its characteristic skin lesions is confined to mutations in the hMSH2 gene.

Adult↗
PubMed1996

FK506 in the treatment of inflammatory skin disease: promises and perspectives.

The immunosuppressive macrolide drug FK506 is currently gaining increasing importance in dermatopharmacology. Here, Gunter Michel and colleagues summarize the current state of research into the molecular mechanisms responsible for the functional modulation of cell types other than T cells, particularly epidermal cells, by this drug.

Animals↗
PubMed1996

Coagulation factor V gene mutation associated with activated protein C resistance leading to recurrent thrombosis, leg ulcers, and lymphedema: successful treatment with intermittent compression.

Activated protein C resistance is the most frequent cause of venous thrombosis. We describe a patient with extensive ulcerations and severe lymphedema of the legs after recurrent thrombosis. Laboratory tests revealed a pathologic activated protein C resistance and a reduced functional protein S. The underlying genetic defect was identified as a heterozygous coagulation factor V mutation. A combined therapeutic approach of intermittent compression, repeated debridements and systemic antibiotics resulted in marked improvement of both lymphedema and leg ulcers.

Anti-Bacterial Agents↗
PubMed1996

Cyclosporin in less common immune-mediated skin diseases.

Cyclosporin represents a major step forward in the systemic treatment of various dermatoses. Psoriasis vulgaris and atopic eczema, the two major indications for the drug, are dealt with elsewhere in this issue. Therefore, this short review will focus on less common inflammatory skin diseases.

Behcet Syndrome↗
PubMed1996

Radioprotective effects of a protein-free hemodialysate in human epidermis.

The accidental or therapeutic exposure of human skin to ionizing radiation is known to cause the radiation syndrome with its various manifestations. The aim of the study was to investigate the potential radioprotective effects of the protein-free hemodialysate Actovegin. After exposure to X-rays (single dose, 6 Gy), 70% of the cells died. In the presence of the hemodialysate, irradiation did not lead to cell death. Instead a slight increase in cell number was observed. A 5-fold increased cell number was found after 6 days when the cells were treated with the hemodialysate alone. To elucidate molecular mechanisms of the observed biological effects the correlation between the expression of the epidermal growth factor receptor (EGFR) and the demonstrated growth activation was investigated. Radiation alone resulted in a clear induction of EGFR, whereas the combination of irradiation and Actovegin treatment led to a strong downregulation after 2 days. Thus, the hemodialysate suppressed one of the radiation-induced effects. Further investigations have to elucidate the role of other proteins which are involved in the signal transduction cascade of tyrosine kinases (e.g. Ras, Raf, MAP kinases) leading to the transcription factor AP-1 in response to radiation under Actovegin treatment.

Cell Count↗
PubMed1996

Characteristic but unfamiliar--the cowpox infection, transmitted by a domestic cat.

An 11-year-old girl had been suffering from 2 recently developed reddish ulcerated nodules on the right side of her neck and, concomitantly, from a very hard swelling as well as from painless lymphadenopathy. Subsequently, thick black eschars appeared on the surface of the ulcers. Using the negative staining technique, an orthopox virus infection could be identified by electron microscopy. The patient's characteristic history as well as her close contact with a cat frequently hunting nice indicated the diagnosis of a cowpox infection, which was unequivocally confirmed by identification of both the viral culture and specific antibodies in the serum of the patient.

Animals↗
PubMed1996

Psoriatic arthritis. New types, new treatments.

Arthritis represents the most common complication of psoriasis, affecting a substantial proportion of patients. Various clinical manifestations are recognized with different prognoses. The clinical spectrum of psoriatic arthritis has been recently extended by newly described entities such as pustulosis palmoplantaris with osteoarthritis sterno-clavicularis and psoriatic onycho-pachydermo-periostitis. Besides methotrexate, cyclosporine has emerged as the drug of choice for the treatment of psoriatic arthritis, since it influences both cutaneous and arthritic manifestations of the disease. New immunosuppressive drugs, such as tacrolimus (FK 506), offer therapeutic promise. Future progress will depend on new insights into the pathogenesis of psoriatic arthritis.

Arthritis, Psoriatic↗
PubMed1996

Cutaneous manifestations of congenital afibrinogenaemia.

Skin problems from coagulation disorders have rarely been described in the dermatological literature. Here we report a patient with a complete congenital absence of fibrinogen which led to leg ulceration, necrosis of the toes and a life-threatening haemorrhage following skin biopsy. This patient shows that leg ulcers may have a complex aetiology and can reflect serious underlying disease.

Adult↗
PubMed1996

Topical calcipotriol in the treatment of intertriginous psoriasis.

The purpose of this study was to examine the effectiveness and side-effects of the vitamin D analogue calcipotriol, applied topically to psoriatic skin lesions in intertriginous areas, in an open and uncontrolled trial. Twelve patients with psoriasis vulgaris who presented with psoriatic lesions in the axilla, and inguinal and anal folds, were treated with calcipotriol ointment (50 micrograms/g) twice daily for 6 weeks. Examination and photographic documentation were performed before treatment, at 3 weeks of treatment, and at 6 weeks of treatment. The mean improvement in the extent and severity of the psoriatic plaques was determined with a semiquantitative grading system closely related to the psoriasis area and severity index (M-PASI). Two of 12 patients showed insufficient response to therapy. Five of 12 patients showed a quick response within 3 weeks or less, and five of 12 patients showed a slow response which could be seen only after 6 weeks of treatment. Minimal burning was reported in one patient, slight lesional and/or perilesional irritation in five patients, and, in the remaining, no side-effects occurred. Topical calcipotriol is an effective and safe treatment for intertriginous psoriasis.

Adolescent↗
PubMed1996

Interleukin-1 receptors type I and type II are differentially regulated in human keratinocytes by ultraviolet B radiation.

Since regulation of keratinocyte IL-1 receptor expression is likely to have a major impact on the biologic effects of IL-1 on epidermal cells, we examined expression, regulation, and function of IL-1R in cultured human keratinocytes. By reverse transcriptase polymerase chain reaction, human keratinocytes were shown to express IL-1 receptor type I (IL-1RI) and IL-1 receptor type II (IL-1RII). Human keratinocyte IL-1RI mRNA expression was dependent on the differentiation state of the cell and was regulated by ultraviolet B (UVB) radiation, which initially decreased but later increased IL-1RI expression. This UVB-induced biphasic modulation of IL-1RI expression was mediated by an autocrine mechanism involving endogenously produced IL-1alpha and IL-1RI. Increased expression of IL-1RI in UVB-irradiated or IL-1alpha-stimulated keratinocytes was functionally important, because it endowed these cells with the capacity to upregulate expression of the intercellular adhesion molecule (ICAM)-1 upon IL-1alpha stimulation. Keratinocyte IL-1RII expression was regulated by UVB irradiation in an inverse manner. Significant and rapid upregulation of IL-1RII was observed within 1 h after UVB irradiation and gradually decreased to background levels within 24 h. Inverse regulation of IL-1RII versus IL-1RI was associated with opposite functions, because blocking of IL-1RII enhanced IL-1alpha effects on induction of ICAM-1 expression. These studies demonstrate that IL-1 responsiveness of UVB-irradiated keratinocytes critically depends on regulation of IL-1RI expression and that IL-1RII serves as a "decoy" receptor for IL-1, limiting rather than promoting IL-1-mediated effects.

Cells, Cultured↗
PubMed1995

[Cutaneous apocrine mixed tumor with follicular differentiation].

An 85-year-old man presented with a firm, papillomatous nodule on the upper lip, which had been growing slowly for 30 years. Histopathologic examination revealed an apocrine mixed tumour with follicular differentiation. Mixed tumours of the skin are rare benign neoplasms, which are composed of different tissue components, e.g. epithelial and glandular elements and myxoid or chondroid components. Mixed tumours with apocrine differentiation can be discriminated from mixed tumours with eccrine differentiation. Criteria for apocrine differentiation are: decapitation secretion, elongated gland-like and duct-like structures lined with two rows of epithelial cells and branching of tubular structures. Follicular structures are another clue to the apocrine differentiation of neoplasms. The designation mixed tumour is preferable to chondroid syringoma, because most mixed tumours show apocrine differentiation. The differential diagnosis of apocrine mixed tumour includes fibroadenoma, hidradenoma, mucinous adenocarcinoma, adenoid cystic carcinoma, and rare soft tissue tumours like the myxoid chondrosarcoma.

Adenoma, Pleomorphic↗