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Biomedical subjects

T Ruzicka

Publications and source records attributed to T Ruzicka.

390 records · Page 22Linked to original sources
PubMedDate not supplied

Andrological investigations in men treated with acitretin (Ro 10-1670).

Ten subjects were treated orally with acitretin (Ro 10-1670) over a period of 3 months. Before, during and after treatment, semen and blood analyses were performed to investigate drug-induced impairment of spermatogenesis and the hypothalamic-pituitary-gonadal axis. Our study concludes that acitretin in therapeutically effective doses does not influence spermatogenesis, sperm morphology, sperm motility and the hypothalamic-pituitary-gonadal axis.

Acitretin↗
PubMedDate not supplied

Increased frequencies of cytochrome P4501A1 polymorphisms in infertile men.

Genetic factors that could mediate the pathogenesis of male reproductive disorders are largely unclear. Polymorphisms of cytochrome P4501A1 (CYP1A1), a key enzyme in the extrahepatic metabolism of lipophilic xenobiotics, have been shown to influence susceptibility to xenobiotics. Here, CYP1A1 polymorphisms were investigated in 134 infertile Caucasian men. The frequencies of the Mspl polymorphism in the 3'-flanking region of the CYP1A1 gene and a mutation in exon 7 causing an isoleucine-valine exchange (IVE) in the heme-binding region of the enzyme were increased among infertile men when compared with those of unselected, healthy male controls (odds ratio (OR)) 1.4, Cl95 0.68-2.89 for Mspl polymorphism; OR 2.4, Cl95 0.83-6.95 for IVE). Patients with normozoospermia revealed the highest frequencies for both polymorphisms (n = 8; OR 4.5, Cl95 0.97-20.91 for Mspl polymorphism; OR 13.7, Cl95 2.53-74.13 for IVE). ORs for the IVE exceeded the values calculated for the Mspl polymorphism. These preliminary results suggest that genetic variation in the metabolism of xenobiotics may codetermine individual susceptibility to infertility.

Cytochrome P-450 CYP1A1↗
PubMedDate not supplied

Microsporum canis infection in a 5-year-old boy: transmission from the interior of a second-hand car.

Microsporum canis is one of the most common zoophilic dermatophytes. If transmitted to humans, inflammatory lesions may develop, e.g. on the scalp. M. canis was isolated from a 5-year-old boy living in a suburban area who suffered from a long-standing, mildly inflammatory lesion on the scalp that had been treated for several months with anti-eczematous regimens. There had been no contact with animals, e.g. cats or dogs, in the previous months, but the lesions had developed a few weeks after the family had bought a used car from a dog owner. Indeed, M. canis could be grown on contact plates from the car's interior. This case illustrates that attention should be paid to the often neglected diagnosis of M. canis-induced tinea capitis and to unusual routes of infection.

Animals↗
PubMedDate not supplied

Gianotti-Crosti syndrome associated with Epstein-Barr virus infection.

Gianotti-Crosti syndrome (GCS) is a distinct exanthematic, acrolocated eruption of childhood caused by a variety of infectious agents. Historically hepatitis B antigen positive (HBsAG+) papular acrodermatitis of childhood and HBsAg negative (HBsAg-) papulovesicular acrolocated syndrome have been distinguished. Here we characterize the spectrum of associated infectious agents in seven patients with confirmed GCS seen in our departments in the years 1994-1995. Where available, stored frozen serum samples were reanalyzed for antiviral antibodies. The mean age of the two girls and five boys was 22.5 months with a range of 8 to 53 months. None of the patients was HBsAG+. Four patients showed serologic evidence of an acute infection and one patient of a recent Epstein-Barr virus (EBV) infection. In two additional children vaccination preceded the appearance of GCS. In these two patients serologic investigations revealed no evidence of recent infection with most common viruses. Our results underline the role of viral infections other than hepatitis B in the etiology of GCS. EBV infection was the most commonly associated viral disease in our population. We agree with other authors that we should avoid using the terms papular acrodermatitis of childhood and papulovesicular acrolocated syndrome in describing HBsAg+ and HBsAg- forms of GCS.

Acrodermatitis↗
PubMedDate not supplied

Green light is effective and less painful than red light in photodynamic therapy of facial solar keratoses.

Photodynamic therapy (PDT) with topically applied delta-aminolevulinic acid (ALA) is increasingly employed to treat patients with multiple solar keratoses and superficial skin tumors. For these indications, ALA-PDT has been shown to be highly efficient. Treatment of multiple or extended lesions, however, is substantially hampered by the fact that ALA-PDT is associated with burning pain during the irradiation procedure. The standard irradiation devices commonly used for ALA-PDT emit red light around 630 nm. In the present half-side comparison study we have observed that ALA-PDT employing a green light irradiation device (543-548 nm) is equally effective, as compared with standard red light ALA-PDT. In contrast to red light ALA-PDT, however, green light ALA-PDT caused only little tingling and burning but no pain. These observations indicate that green light ALA-PDT is superior to standard ALA-PDT, because it is associated with less unwanted side effects.

Aged↗
PubMedDate not supplied

Porphyria cutanea tarda.

Porphyria cutanea tarda (PCT) is the most frequent form of porphyria. The underlying enzymatic defect in PCT is a reduced activity of the enzyme uroporphyrinogen decarboxylase (Uro-D). Four different types of Uro-D disturbances are known. Pseudoporphyrias such as porphyria cutanea uraemica or drug-induced PCT-like skin symptoms are distinguished from PCT. Porphyrinogens such as estrogens or alcohol, or other inducers of P450 isoenzymes provoke PCT. Polymorphisms of P450 isoenzymes, iron overload and infection with hepatitis C virus play an important role in the etiopathogenesis of disease manifestation. Dominant clinical symptoms are bullae, increased cutaneous vulnerability, hypertrichosis and elastosis. Biochemically, total porphyrin levels in urine are increased with a predominance of uroporphyrin and heptacarboxylic porphyrin. Isocoproporphyrin is demonstrable in feces. Best therapeutic strategies are the oral administration of chloroquine 125 mg twice a week and repetitive bloodlettings or the combination of both.

Coproporphyrins↗
PubMedDate not supplied

Congenital erythropoietic porphyria.

Congenital erythropoietic porphyria (CEP) is one of the rarest autosomal-recessive disorders of the porphyrin metabolism caused by the homozygous defect of uroporphyrinogen III cosynthase. High amounts of uroporphyrin I accumulate in all cells and tissues, reflected by an increased erythrocyte porphyrin concentration and excretion of high porphyrin amounts in urine and feces. Dermal deposits of uroporphyrin frequently induce a dramatic phototoxic oxygen-dependent skin damage with extensive ulcerations and mutilations. Splenomegaly and hemolytic anemia are typical internal symptoms. Skeletal changes such as osteolysis and calcifications are frequent. Up to date 130 cases of CEP have been published. Splenectomy and erythrocyte transfusions showed some beneficial effect. Bone marrow transplantation was performed in 3 patients and stem cell transplantation in 1. The best therapy is the avoidance of sunlight. We give a report on our latest cases of CEP.

Adolescent↗
PubMedDate not supplied

Photodynamic diagnosis and therapy in dermatology.

The topical application of delta-aminolevulinic acid (ALA) induces porphyrin formation in the skin, preferentially in tumor tissues. Irradiation of the porphyrin-enriched tumor tissue with Wood's light leads to emission of a brick-red fluorescence. This principle may be used as a diagnostic procedure which may be termed photodynamic diagnosis (PDD). In ALA-PDD, tumors and precancerous lesions of the skin reveal a homogeneous, intensive red fluorescence. Psoriatic lesions also show a strong but inhomogeneous porphyrin fluorescence. ALA-induced porphyrin fluorescence in preoperative planning is a valuable method to determine the peripheral borders of a given tumor. The histopathological extensions of the tumors correlate well with the borders detected by the tumor-specific fluorescence. The main indications of PDD are the delineation of clinically ill-defined skin tumors and the control of the efficacy of other tumor therapies. Photodynamic therapy (PDT) utilizes exogenously applied or endogenously formed photosensitizers and their activation by light to induce cell death via formation of singlet oxygen and other free radicals. PDT is highly efficient in the treatment of solar keratoses and superficial basal cell carcinomas. Initial squamous cell carcinomas also show good response to ALA-PDT. During the last decade, numerous studies on PDT for dermatologic diseases were published, the more important ones are reviewed here.

Aminolevulinic Acid↗
PubMedDate not supplied

Modulation of atopy patch test reactions by topical treatment of human skin with a fatty acid-rich emollient.

Measures directed at improving the skin barrier function are thought to be effective in preventing reexacerbation of atopic dermatitis, but direct proof of a prophylactic effect of emollients has been elusive. In the present study, the atopy patch test has been employed as a model for the initiation phase of atopic dermatitis in order to assess whether pretreatment of non-lesional skin with a fatty acid-rich emollient (Eucerin Omega Creme) has a prophylactic effect in patients with atopic dermatitis. Pretreatment of test sites with Eucerin Omega Creme either prevented or diminished the development of eczema, as compared with untreated control test sites in the same patients (n = 38). These studies indicate that the use of fatty acid-rich emollients prevents the development of atopic eczema. They also demonstrate that the atopy patch test can be used to assess the capacity of a given regimen to exert prophylactic effects in this disease.

Adult↗
PubMedDate not supplied

Penetration kinetics of 8-methoxypsoralen after 8-methoxypsoralen bath procedure with and without UVA irradiation.

Administration of 8-methoxypsoralen (8-MOP) in a dilute bath water solution is an effective therapeutic alternative for systemic application of 8-MOP, avoiding systemic side effects such as nausea and cataractogenesis. The aim of our study was to determine the epicutaneous penetration of 8-MOP in a dilute bath water solution with and without additional UVA irradiation in human skin under in vitro conditions. To simulate the PUVA bath procedure, 8 skin samples were exposed to radioactively labeled 8-MOP in a water solution. After 20 min, the test solution was removed and the skin surface was dried. Immediately after the bath procedure, 4 of the skin samples were irradiated with 0.5 J/cm2 UVA. During a test period of 15 h, the 8-MOP penetration was observed. In both test groups (with and without UVA irradiation) 8-MOP permeated through all skin layers between 30 min and 1 h after application. Compared to the unirradiated skin samples, the UVA-irradiated skin samples showed a significantly slower increase and a lower maximum of 8-MOP permeation. Following our results, UVA irradiation of 8-MOP-exposed skin samples led to a significantly decreased permeation rate. This might be due to UVA-induced links between 8-MOP molecules and human DNA. In addition, we investigated the levels of radioactivity emitted by tritium-labeled 8-MOP in stratum corneum, epidermis and dermis up to 30 min after 8-MOP bath in two further test groups with and without additional UVA irradiation. The statistical analysis revealed no significant differences between these two test groups. Thus, the levels of radioactivity remained constant in the epidermis and dermis during the test period of 30 min. Since the levels of radioactivity were constant up to 30 min after UVA irradiation, a previously supposed marked loss of 8-MOP concentration might not be responsible for the rapid extinction of observed in vivo photosensitivity within 1 h after PUVA bath observed in vivo in human skin.

Adult↗